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Integration period

50 msec

. . .

Calculations

10 msec (nom.)

RS-232 Pressure Reading Output

16.7 msec

msec

50 msec

. . .

(Integration Time = 50 msec, I=R20)

(See Tables 7.1 and 7.2 for X times)

Figure 7.4—Timing Diagram for 20 Readings Per Second

When I=R31 (or more) mode:

Integration period

20 msec

Calculations

20 msec

10 msec

20 msec

10 msec

. . .

10 msec

. . .

RS-232 Pressure Reading Output

msec

20 msec

. . .

(Integration Time = 20 msec, I=R50)

(See Tables 7.1 and 7.2 for X times)

Figure 7.5—Timing Diagram for 50 Readings Per Second

Integration period

8.3 msec

Calculations

8.3 msec

6-7 msec

8.3 msec

6-7 msec

. . .

6-7 msec

. . .

RS-232 Pressure Reading Output

msec

8.3 msec

. . .

(Integration Time = 8.3msec, I=R120)

(See Tables 7.1 and 7.2 for X times)

Figure 7.6—Timing Diagram for 120 Readings Per Second

7 7

Summary of Contents for PPT

Page 1: ...Honeywell Precision Pressure Transducers PPT and PPTR User s Manual ...

Page 2: ... and recording for any purpose without the express written permission of Honeywell Inc Honeywell reserves the right to make changes to any products or technology herein to improve reliability function or design Honeywell does not assume any liability arising out of the application or use of any product or circuit described herein neither does it convey any license under its patent rights nor the r...

Page 3: ...t 4 2 6 Step By Step Examples 5 2 7 Command Functional Groups 7 3 COMMANDS QUICK REFERENCE 9 4 FUNCTIONAL OPERATION 13 4 1 Overview 13 4 2 What Is Integration 14 4 3 Pressure Reading Control 14 4 4 Output Voltage Control 16 4 5 Pressure Window Control 16 4 6 Customized Pressure Range 17 4 7 Setting Pressure Set Points 18 4 8 PPT Analog Output Configurations 19 4 9 Command Illustrations 20 4 10 Pre...

Page 4: ...on Directing Commands 29 5 4 Command Replies General 29 5 5 ASCII Format Replies 30 5 6 Binary Format Replies 31 5 7 Command And Reply Sequencing 34 5 8 Command Errors 35 5 9 Command Summary Table 37 5 10 Command Descriptions 39 6 ELECTRICAL CONNECTIONS 73 7 TIMING DIAGRAMS 75 8 SPECIFICATIONS 78 9 DIMENSIONS 80 ii ...

Page 5: ...e 1 20 Integration I Command Example 2 21 S2 Speed Shift Command Example 21 S5 Speed Shift Command Example 22 Deadband and Integration DI Command Examples 22 23 Idle Count IC Command Example 23 Synchronize Integration Cycles SI Command Example 24 RS 232 PPT Ring Network 25 RS 485 PPT Multidrop Network 26 Single PPT Command and Reply 34 Multiple PPT Network Command and Replies 35 PPT Electrical Con...

Page 6: ... Setup Commands 20 Decimal Place Locations for Pressure Readings 24 Header Description for Binary Format Pressure Readings 31 Binary Format Character Codes 33 Command List 37 Command Factory Default List 39 Display Units Options 47 Transmission Times at Selected Baud Rate 77 Number of Bytes in Various Replies 77 ASCII Conversion Table 81 RS 232 Standard Pin Connections 81 Electrical Signal Levels ...

Page 7: ... detailed description of the command structure func tional groupings and all user commands Section 6 Electrical Connections Contains wiring diagrams for various PPT electrical connections Section 7 Timing Diagrams Illustrates RS 232 serial port timing for command and reply interaction Section 8 Specifications Contains electrical and environmental specifications Section 9 Dimensions Contains a case...

Page 8: ...s Group multicast addressing allows up to nine groups of PPTs to be addressed with a single command Global broadcast addressing will send a command to all PPTs on the serial bus Any computer having a serial port and terminal emulation software can be connected to the PPT to allow the user to select baud rates sample rates readout resolution units of pressure and other choices Analog output from th...

Page 9: ...e Output A five digit voltmeter with 0 5 volt range connected between Analog Out and Signal Common A computer is not required when operating in this mode To operate the PPT in the digital output mode one additional item is needed A computer or host processor having an RS 232 or RS 485 serial port and terminal program software such as PROCOM VERSATERM TERMINAL Windows 3 x or HYPERTERMINAL Windows 9...

Page 10: ...lt address device called a null address This PPT has not yet been assigned an ID number so it assumes the null address The PPT____10__psid indicates a 10 psi differential device 2 5 COMMAND FORMAT Any command interaction with the PPT requires electrical connection to the RS 232 or RS 485 serial communications pins There are two basic types of commands action directing commands and information requ...

Page 11: ...The CP 15 458 indicates a compensated pressure of 15 458 psi Your unit may not show this specific reading depending on the applied pressure it is measuring SET DEVICE ID To give the PPT an assigned address of 01 up to 89 enter the following commands Type 00WE cr This enables the PPT to change a parameter in RAM Type 00ID 01 cr This sets the null addressed PPT to device ID 01 Note The device ID is ...

Page 12: ... Each integration period gathers the data for one pressure reading output see Section 4 2 What is integration The range of integration times can be set by specifying readings per second I R45 for 45 read ings sec or time delay in 100 millisecond intervals I M60 for 6 seconds The factory set inte gration time is 5 samples per second I M2 The output data rate can also be altered by use of the idle c...

Page 13: ...erature readings C T4 Continuous RS 232 temperature readings F Integration Time Commands Changes pressure reading response time DS Set deadband and sensitivity parameters I Set pressure integration time and reading rate S2 Set threshold level for 2X speed shift S5 Set threshold level for output within any 50 msec period SI Synchronize pressure Integration cycles Idle Count Command Changes pressure...

Page 14: ...r indicators C K Performs and provides the result of EEPROM checksum OP Use pressure reading checksum for binary format OFFSET TARE CONTROL T Allows user to install an offset in the output reading TC Turn on or off user controlled tare function USER AND STARTUP MESSAGES A Store 8 characters of user supplied data B Store 8 characters of user supplied data C Store 8 characters of user supplied data ...

Page 15: ...an be used for a watchdog or reset message 00C This_is_ see MO command D A Digital and Analog Control D O Default Operating Parameters Inquiry 00C 00WE Turn on analog output only 00DA A Inquiry 00DA Set DO parameters 00WE factory default setting 00DO E Inquiry 00DO 01C This_is_ 01DA A 01DO E0N D S Deadband and Sensitivity Control Set DS parameters 00WE set deadband to 20 x 0 005 0 10 FS 00DS 20 In...

Page 16: ...e to 50 readings second 00I R50 L Lowest Analog Output Voltage Inquiry 00I Set L parameter 00WE 01I R050 set analog low value to 28 x 5V 1 4V 00L 28 Inquiry 00L M Maximum Full Scale Value Allowed Factory set Inquiry 00M M O Power Up Mode Set MO parameter 00WE 00MO M1 00WE Required to save in EEPROM for power up 00SP ALL Inquiry 00MO N E Digital Input Enable to Analog DAC Output Set a DAC analog ou...

Page 17: ...Inquiry 00RR RS Read Status Inquiry 00RS S2 Speed Shift to 2X Set S2 parameter 00WE shift to double speed if pressure changes 00S2 12 more than 12 0 01 FS 0 12 FS Inquiry 00S2 S5 Speed Shift at 50msec Intervals Set S5 parameter 00WE Output reading if pressure changes 00S5 60 more than 60 0 01 FS 0 6 FS Inquiry 00S5 S I Synchronize Pressure Integration Synchronize Integration 01SI SP Store Paramete...

Page 18: ...ndow width to 40 x 20 psi FS 8 psi 00W 40 set analog set point 00W S X Y Slope User Compensation Control Inquiry 00W Set X parameter 00WE 01W 40 set user slope control to 0 005 x 17 0 085 FS 00X 17 Inquiry 00X 01X 17 Note The input slope and offset control are for user supplied mx b correction The Y is for negative slope for differential units Z Offset User Compensation Control Set Z parameter 00W...

Page 19: ... 5 volt range in 1 increments Those who choose to use the factory set defaults may use the analog output without ever connecting to a computer The analog output is driven by a 12 bit digital to analog converter DAC Because the PPT has an internal EEPROM Electrically Erasable Programmable Read Only Memory to store configuration settings it can replace conventional analog transducers without connect...

Page 20: ...o 120 samples sec using the I Rn form or a range of 100msec to 12 sec sample using the I Mn form The values for n range from 1 to 120 for both the rate Rn form and the millisecond Mn form The speed shift commands can only be enabled when the integration time is set using the I Mn form When enabled the thresholds for pressure change can be set that cause the output rate to double S2 or update at 50...

Page 21: ...tion Time if I Rn if I Mn DAC Analog Output A D Converter Dead Band DB n x dd x 0 005 FSrange dd 0 60 n 1 2 4 or 8 X nn Y nn Z nn X Y 1 000 factory default Display Units and Tare Digital Analog Select Output levels Offset Window H L O W Integration Output Control PPT supplied value Digital and Analog Control S2 causes output rate to double speed S5 causes output changes every 50 msec Display Units...

Page 22: ...Set Output Levels The AN command has two options for reverse scale output AN ON and AN OFF When either option is selected the lowest pressure will output the highest analog voltage H and the highest pressure to output the lowest analog voltage L Notice that the input pressure vs output voltage curves in Fig 4 3 look similar But note that the pressure values along the pressure axis have been revers...

Page 23: ... Z and F commands The X command adjusts the slope of the pressure output curve for positive pressures This applies to all absolute and gauge devices and modifies the positive full scale slope of PPTs The Y command adjusts the negative full scale slope of differential PPTs The Z command adjusts the offset of the pressure output curve The range of adjustment for X Y and Z commands is 0 6 FS in 0 005...

Page 24: ...y to program an analog pressure set point that triggers the analog output from the low voltage setting L to the high voltage setting H using the W and O commands These outputs can be used to activate alarms or lights based on pressure conditions This feature can operate in an analog only mode once the set point has been configured and stored to EEPROM The set point can be changed in the applicatio...

Page 25: ...control processor can control the analog output voltage from the PPT independent of the pressure readings This capability allows a single PPT unit to operate in a closed loop mode for systems requiring valve control Figure 4 11 PPT Pressure Readings and Analog Voltage Control Two PPTs can be used to sense pressure at one location and drive the analog pressure output at a remote location without a ...

Page 26: ...in transmitting and outputting analog readings when power is applied see Table 4 1 To connect additional PPT pairs to the RS 232 bus configure each pair with a unique group number Nine groups are available from number 90 through 98 The example shown in Table 4 1 assumes both PPT units are in the same group factory default group is 90 Commands to setup PPT1 Commands to setup PPT2 Input Comment Inpu...

Page 27: ...ands The Speed Shift commands S2 S5 allow the tracking of rapid changes while sampling less often when pressures are slowly changing A threshold is set independently for the S2 and S5 commands that tell the PPT when to begin outputting samples at the higher rate The S2 command causes the output rate to double The S5 command causes the readings to be output at 50 msec intervals synchronous with the...

Page 28: ...C command for four different pressure curves The IC command does nothing more than skip over a set number of readings If the idle count were set to IC 4 then after a pressure output reading the PPT would not output the next 4 readings and the fifth one would become the next output reading This feature allows the reading rate to be estab lished different from the integration time This feature is us...

Page 29: ...ption with a 10x multiplier For a 20 psi full scale device this results in a 0 40 psi deadband window 1 0 3 0 5 0 Time sec Pressure Figure 4 17b Deadband and Sensitivity DS Command Examples Idle Count 5 24 5 20 5 16 5 12 5 08 5 04 psi IC 11 skip 11 IC 4 skip 4 IC 2 skip 2 IC 0 skip none I M2 RR 0 S2 0 S5 0 OP A 5 00 4 96 4 92 12 3 4 5 6 7 8 91011 1 2 Integration time PPT pressure output Actual pre...

Page 30: ...the number of digits to the right of the decimal place This is valuable when converting a binary format number so that decimal position can be determined For pressure values less than 1 0 XXXX the first character of the pressure reading will be a zero if positive 0 XXXX or a minus sign if negative XXXX For pressure values XX XX greater than 1 0 the first character will be a space or a number if po...

Page 31: ...nd A unit responds to its group address in the same manner as it does to its global address described below The group addressing allows the host proces sor to send commands to several units having the same group address The factory default group address is 90 The highest level of addressing is the broadcast or global address 99 All units receive global addressed commands All RS 232 units respond t...

Page 32: ...command types Every unit in the RS 232 ring network receives a global addressed 99 command All units read the command and pass the command and their response to the next unit in the ring The sequential response is the same as for the group command described above See Table 5 3 for sequential command types RS 485 Multidrop Network The RS 485 network consists of a two wire bus A and B that begins at...

Page 33: ...ives all commands If the command has a group or global address requiring a response the PPTs addressed will wait until the unit with the next lower address responds before sending its response If the command had a global address 99 then the PPTs will respond in the order of the assigned device IDs If the command had a group address 90 to 98 then the PPTs will respond in the order of the assigned g...

Page 34: ...d mode P2 P4 T2 T4 the special header character should be used to suspend all PPT transmissions while the command message is being typed The is immediately followed by the normal command format Also for RS 232 mode if an erroneous command is sent to the PPT it is echoed back to the host in the same form it was sent The only exception to this is when a group or global address command ID 90 to 99 is...

Page 35: ...ting parameter s and is provided as a safeguard to prevent inadvertent changes The only exception to this is the initialization IN command which is activated upon receipt COMMAND REPLIES GENERAL Replies are transmitted from the PPT in response to an information request inquiry or due to a power applied condition All replies end with a cr carriage return character which can be used as a delimiter t...

Page 36: ...d Information Interchange The ASCII format consists of standard keyboard alpha numeric characters and symbols The header character is the first character in the reply from the PPT The ASCII format information request reply uses the following header charac ters ASCII format reply from an assigned address PPT ASCII format reply from a null address PPT Example replies to command code cc are where xx ...

Page 37: ...pace or Blank 5 6 BINARY FORMAT REPLIES The binary format reply is only used for the pressure reading commands P3 and P4 It consists of a 1 byte header character 4 bytes data an optional 1 byte cyclic check sum and 1 byte cr character For the binary format replies the address type error condition and data sign are encoded into the single header character as shown in Table 5 1 below Header Assigned...

Page 38: ...form or the extended form by using the OP command The 24 bit binary forms are Extended 7 bit binary device address 17 bit binary pressure data Signed 7 bit binary device address sign bit 16 bit binary pressure data Example binary reply 16 cr Refer to Table 5 1 for the header character definition The sign of this pressure value is determined by the header character The next 4 characters 16 contain ...

Page 39: ...10 1111 101010 101011 101100 101101 101110 101111 P Q R S T U V W X Y 80 50 0101 0000 81 51 0101 0001 82 52 0101 0010 83 53 0101 0011 84 54 0101 0100 85 55 0101 0101 86 56 0101 0110 87 57 0101 0111 88 58 0101 1000 89 59 0101 1001 010000 010001 010010 010011 010100 010101 010110 010111 011000 011001 0 1 2 3 4 5 6 7 8 9 48 49 50 51 52 53 54 55 56 57 30 0011 0000 31 0011 0001 32 0011 0010 33 0011 001...

Page 40: ...D 01 Group 90 T RS 232 Transmit R RS 232 Receive COMMAND Power on 01S 99we 99id 01 01P1 01ID Processor R REPLY 01PPT____20_psia 01S 00036714 99WE 99ID 02 01CP 12 345 01ID 90 COMMENT factory set power on message Read factory set serial number RAM or EEPROM write enable global Set device IDs global Read pressure from device ID 01 Read group number Figure 5 1 Single PPT Command and Reply When several...

Page 41: ...or global address 90 to 99 then the command has been rejected due to an incorrect header address number command code or action character This error is common if an incorrect command code format was used or if the command should have been preceded by a write enable WE NE command and was not If the command was rejected because of an incorrect command code or action character an error indicator is se...

Page 42: ... group or global com mand This is a sequential response After The PPT response is sent after the group or global command No The PPT just passes the command through the network with no response Input or Output Is information input to the PPT or output from the PPT In Com mand is only used to input action direct command to the PPT Out Command is only used to output request information inquiry from t...

Page 43: ...4 Both Yes 6 No No 11 Yes 13 Offset a custom analog output range OP Yes Before Both Yes 6 No No 11 No Set operating mode parameters P P1 P2 P3 P4 No No No 3 No No 3 After 4 Before 5 After Before 5 After Out Out Out Out Out No No No No No No No Yes 9 No Yes 9 No No No No No No Read PPT production date No Single pressure reading ASCII No Continuous press reading ASCII No Single pressure reading bina...

Page 44: ... sequential response is when the PPT reply is sent before the global or group command through the network See the individual command descriptions for detailed information 6 These commands only require a write enable WE when used in the action directing form For these commands the WE command provides a single occurrence write enable for RAM update That is only the next instruction is written to RAM...

Page 45: ...9 cc is the command code The command code characters may be one letter two letters or a letter and a number The letters are not case sensitive i e either upper case or lower case may be used The PPT will convert the character to upper case equal sign required in some commands nnn additional characters required in some commands cr carriage return ENTER key must follow every command Commands are not...

Page 46: ...g range setting is established with the H and L commands Analog window settings are established with the O and W commands When AN is ON the customized settings are activated when OFF the factory default range of 0V to 5V is active When custom H and L range settings are used the resolution of the analog signal will be reduced For example the full 5 volt range has a 12 bit resolu tion A range reduct...

Page 47: ... of manual B P Baud Rate and Parity Setting The Baud rate and Parity command is used to change the baud rate and parity type Both the write enable WE and BP command must be sent as a global address e g 99 otherwise the command is rejected and sets the read status RS command error For this command only the first one or two baud rate characters need to be used This command causes the new baud rate a...

Page 48: ... used to provide the first eight characters of a user provided start up message see the MO command When used as a start up message any space character in the C message will terminate the message Use an underscore _ character for spaces Inquiry dd C Action ddWE ddC Your_msg Your_msg must have 1 to 8 characters immediately following the character The message is terminated with the cr character The l...

Page 49: ...sponse has an character instead of there was an EEPROM parity error Note This command will not work when a ddWE RAM continuous write enable is active It must be preceded by a singular write enable ddWE Note This data can be used to provide the last eight characters of a user provided start up message see the MO command When used as a start up message any space character in the D message will termi...

Page 50: ...log A Commands P1 P2 Commands P3 P4 Disabled 1 Disabled 2 Output Voltage Tracks Pressure B 5 C D 5 E 5 F 5 G 5 M N O R 5 S 5 T 5 U 5 ASCII Format Disabled 1 ASCII Format ASCII Format Disabled 1 Disabled 1 ASCII Format Disabled 1 Disabled 1 ASCII Format Disabled 1 ASCII Format ASCII Format Binary Format Binary Format Binary Format Disabled 2 Binary Format Binary Format Disabled 2 Disabled 2 DAC Val...

Page 51: ...e PPTs are on the bus the correct number is calculated by dividing the number of PPTs by 10 and rounding up to the next whole number N Normal operation P Noise protection when running in the P4 continuous mode This option reduces the chance that noise will cause transmission to stop during continuous P4 pressure readings In this mode the PPT will respond normally to computer sent commands that are...

Page 52: ...ultiple pressure samples are used to determine a single pressure reading If one of the samples falls outside the deadband limits and the average of all the samples falls inside the limits then the transmitted reading will be inside the limits To avoid this effect set the integration time to I R61 or greater Now the transmitted pressure output will be based on a single sample When the W S command i...

Page 53: ...orr MPA 0 0068948 megapascal MWC 0 70304 meters of water column 4 C PSI 1 0000 pounds per square inch USER 0 0010000 999 99 user supplied see also U command LCOM FS 60000 logic common value 2 PFS FS 100 000 percent of full scale in 0 001 increments Table 5 5 Display Units Options 1 From the CRC Handbook Of Tables For Applied Engineering Science 2 TheLCOM display unit logic common automatically swi...

Page 54: ... DU inquiry Action ddWE EEPROM Store ddWE ddF FSnum ddSP ALL FSnum This value can have up to 5 significant digits with a decimal point First select the display units desired except for LCOM USER or PFS using the DU command H Highest Analog Voltage Set the DAC High analog output voltage full scale FS reading The input is a value from 0 to 99 of 5 volts or 50 millivolts per count An H inquiry reads ...

Page 55: ...ets the output sample time in 100 Millisecond incre ments 0 1 seconds This allows output rates from 10 readings per second up to 1 reading every 12 seconds I M0 will restore the last setting saved in EEPROM Idle Count Parameter The Idle Count parameter specifies the number of pressure integration times that the microproces sor skips between output values see Fig 4 18 This command is only operation...

Page 56: ...mber 00 99 must enter a TWO digit decimal number where 00 Unit numbers itself 00 null address and transmits the message unchanged A 99ID 00 will change all PPTs in network to null address see Note above 01 88 Unit numbers itself with device ID newNumber increments the number by 1 and transmits the message This will sequentially number all PPTs in a network starting from unit dd with ID newNumber s...

Page 57: ...99WE 99ID 02 02WE 02SP ALL When the identification address has been assigned group address and sub address can be assigned in the same manner as in 1 above Note For RS 485 units all 9xID commands are ignored unless the command has been preceded by a serial number command 99S ssssssss with the serial number that matches that unit The next 9xID command will set that unit s device ID number I N Initi...

Page 58: ...ing voltage of 0 75 volts 15 x 50mV or 15 of 5 00V For L 0 the low voltage will be 0V For L 99 the low voltage will be 4 95V M Maximum Customized Full Scale This command identifies the Maximum full scale pressure in psi units that can be user customized see F command This value is fixed at the factory and corresponds to the full scale reference value for accuracy and error determination If the res...

Page 59: ...e if a space is desired Inquiry ddM O Action ddWE ddMO X2 P2 P4 T2 T4 or EEPROM Store ddWE ddSP ALL ddMO M0 M1 M2 M3 N0 N1 N2 N3 X2 No continuous readings P 2 Continuous pressure readings in ASCII format P 4 Continuous pressure readings in binary format T 2 Continuous Celsius temperature readings T 4 Continuous Fahrenheit temperature readings Note To use the P2 P4 T2 or T4 commands on RS 485 units...

Page 60: ...in millivolts N 4000 for 4 000 volts or in millivolts to the tenths of millivolts digit N 4234 1 for 4 2341 volts The value dddd will be modified by the O W H or L commands if they are activated N E Analog Output Enable The aNalog Enable command allows the host processor to control the DAC analog output This command is used to enable the N command and the binary form command for direct DAC con tro...

Page 61: ...ion of the remaining range is of interest If the range of 4psi to 16psi is desired to be windowed onto the 0 to 5 volt scale then a W 60 would be used 60 of 20 12 psi 4 psi 16 psi FS If a 20 psid unit had the offset pressure window set to O 20 then the offset pressure would be 8 psi 20 of 40 psi The analog 0V output would begin at 12 psi cross 2 5V at 4 psi and output 5V at 20 psi If the W value w...

Page 62: ...s the 6 least significant bits of the result will be zeroes see Table 5 2 for the list of characters to be used E Extended form for the commands P3 P4 using the binary format This yields a 7 bit binary device address and a 17 bit magnitude for the pressure reading The pressure sign is encoded in the header character This allows up to 90 000 counts in the pressure A D conversion cycle and allows di...

Page 63: ...ressure is at zero and a temperature over under range occurred or there is an EEPROM parity error Check RS for specific error If a parity error occurred then send a ddIN RESET command or cycle the power off and on A response of 01CP indicates that no pressure reading is available yet Try again This response can be a result of a P1 request after a DU BP parity change or ID action command or during ...

Page 64: ...ry format compensated pressure reading not available yet xx_ request again or it has been disabled The xx is the header character and the 6 most significant bits of the address P 4 Pressure Continuous Binary Format The P4 command produces a continuous stream of temperature compensated pressure readings in a 6 byte binary format a 1 byte header character 4 bytes encoded address and pressure data an...

Page 65: ...anges and deadband is controlled by the DS command Default RR 0 Note This command is only operational when OP U is used Inquiry dd RR Action ddWE ddRR readRate readRate 0 to 10 where 0 Transmit every reading EEPROM Store ddWE ddSP ALL 1 10 Requests that readRate x100 identical readings be skipped after each transmission When this number has been reached the current pressure reading is transmitted ...

Page 66: ...y error EEPROM parity characterization checksum error EEPROM parity control checksum error EEPROM parity characterization control error EEPROM parity error for A B C D M P S and start up header response No DAC write checksum error or command error Command error DAC write checksum error Both DAC write checksum error and command error RS 232 framing error RS 232 parity error Both RS 232 framing and ...

Page 67: ... with a group or global address sequential mode only PPTs which have at least one error condition will respond Replies are in sequential RS 232 bus loop connection order followed by the return of the RS command Out of range temperature has display precedence over out of range pressure which in turn has precedence over microprocessor bandwith warning which is followed in precedence by noisy signal ...

Page 68: ...mber must be used because the identification match is made on all 8 ASCII characters not the decimal value of the serial number identifies the PPT for identification address assignment The address assignment is then performed by a 99IDnn com mand where nn is the address Note If two PPT units on a RS 485 bus have the same ID then you can use the sequence below to re assign ID numbers Action 99WE 99...

Page 69: ...operational when the I Mn form of the Integration command is used See Figure 4 16 for command illustration Default S5 0 Inquiry ddS5 Action ddWE EEPROM Store ddWE ddS5 thresholdS5 ddSP ALL thresholdS5 0 to 15 where 0 Disable the S5 speed shift function 1 15 Sets the speed shift threshold for 50 msec intervals at thresholdS5 x 0 01 FS reading times threshold 0 01 FS x thresholdS5 Synchronize Integr...

Page 70: ... a tare Setting the tare is similar to setting an offset pressure An example would be going to the delicatessen and weighing the empty container before filling it A tare is set to offset the weight of the container so that it is not included in the final weight Note Tare does not affect the analog outputs see Figure 4 2 Inquiry ddT Action ddWE ddT SET TareValue EEPROM Store ddWE dd SP ALL S E T Se...

Page 71: ...g The reading resolution is 0 1 degrees C Default see T1 command Inquiry ddT2 Type 99IN To stop the continuous temperature reading command Note For RS 485 units when the continuous transmit parameter is NOT active is not set to TO C the T2 command sends only one reading Note For RS 232 units type a 99IN to stop this command The character suspends the tem perature readings while the 99IN command di...

Page 72: ...er is NOT active is not set to TO C the T4 command sends only one reading Note For RS 232 units type a 99IN to stop this command The character suspends the tem perature readings while the 99IN command disables the continuous output T C Tare Control Switch The Tare Control command turns on or off the user controlled tare zero offset function When ON the setting established by the T command is used ...

Page 73: ...S 485 unit to transmit Continuous pressure readings P2 or P4 when the device ID is used This parameter has no effect on RS 232 units A RS 485 only Causes the SI command to start a pressure integration cycle and not clear the result of the previous cycle so it can be read with a P2 or P4 command if the result has not been previously read When the synchronized cycle completes a new cycle is immediat...

Page 74: ...e device IDs or group sub addresses were not sequential beginning with number 01 U User Supplied Display Units The User supplied display units command allows the user to enter units of measure for the PPT The value entered for this command is multiplied by the actual pressure in psi to get the user defined units For example if ddU 15 0 cr then the compensated pressure output values will be 15 time...

Page 75: ... the pressure window would be 24 psi 60 of 40 psi The analog 0V output would begin at 20 psi cross 2 5V at 8 psi and output 5V at 4 psi If a window offset of O 20 was set then the analog 0V output would begin at 12 psi cross 2 5V at 0 psi and output 5V at 12 psi If an O value is set 40 then it is automatically set to 40 Note Setting a pressure window W value that causes the maximum output pressure...

Page 76: ... commands following a ddWE RAM will be stored in RAM A ddWE command will disabled or deactivate this permanent RAM write enable The ddWE RAM command will not allow the SP command to write to EEPROM Action ddWE OFF This immediately disables the ddWE RAM condition X Slope 1 User Compensation Control The user can adjust the pressure vs output curve using the X Y and Z commands The X command adjusts t...

Page 77: ...fset null can be set by applying equal pressure to both ports and execute a Z CAL command For PPTR s the Z command should be used to account for mounting orientation The PPTR s have an oil filled stainless steel diaphragm that protects the sensor from corrosive media This oil fill will cause an offset in pressure reading when the PPTR is mounted in any position other than horizontal A method of ca...

Page 78: ...al reading value Per form an EEPROM store to make the correction permanent Note For gauge type PPTRs the orientation offset is corrected with the Z CAL command after the unit has been mounted in its application orientation Suspend Continuous Readings This is not actually a command but a special command header character During a continuous pressure reading command P2 or P4 in RS 232 ring configurat...

Page 79: ... are formed 0000001 01010011000000100 Grouping this string into four 6 bit groups gives 000000 101010 011000 000100 Converting these to printable characters using Table 5 2 give the four byte string jXD Therefore the command jXD cr will set the DAC output to 4 2500 volts when DA G N or R and the NE DAC is enabled Note The PPT transmits command data when DA O S T or U and a P3 or P4 is activated Th...

Page 80: ...ltage Output PPT Plastic Mating Connector Conxall P N 6 282 6SG 522 Newark Stock no 89F4115 PPT and PPTR Metal Mating Connector ITT Cannon P N MS3116F10 6S Newark Stock no 93F3377 Figure 6 1 PPT Plastic PPT Metal and PPTR Electrical Connector Pin Assignments Figure 6 2 Connection for RS 232 Operation and Analog Output 7 4 PPT metal connector PPTR pins top view PPT plastic connector pins top view ...

Page 81: ...ower In Voltage Output 2 3 4 5 6 Make all common connections at this end of the cable Battery 5 5 to 30V Common 0 to 5 VDC Out Figure 6 4 Connection for Analog Output and Battery Operation Host Computer RS 232 TD RS 485 B RS 232 RD RS 485 A Case Ground Power and Signal Common DC Power In PPT Voltage Output Actuator or Valve 1 2 3 4 5 6 shield gnd Make all common connections at this end of the cabl...

Page 82: ...gure 7 1 Default Single Pressure Reading Timing Diagram When I Mn mode or I R30 or less mode For continuous pressure reading commands P2 and P4 the PPT internal times and the output timing are shown Figure 7 2 Integration period 200 msec 200 msec 200 msec Calculations 10 msec nom RS 232 Pressure Reading Output 16 7 msec X msec 200 msec See Tables 7 1 and 7 2 for X times Figure 7 2 Default Continuo...

Page 83: ...d 20 msec Calculations 20 msec 10 msec 20 msec 10 msec 10 msec RS 232 Pressure Reading Output X msec 20 msec Integration Time 20 msec I R50 See Tables 7 1 and 7 2 for X times Figure 7 5 Timing Diagram for 50 Readings Per Second Integration period 8 3 msec Calculations 8 3 msec 6 7 msec 8 3 msec 6 7 msec 6 7 msec RS 232 Pressure Reading Output X msec 8 3 msec Integration Time 8 3msec I R120 See Tab...

Page 84: ...2 max length T1 T2 T3 T4 Other Replies 1 Includes cr character of Characters 1 6 7 12 16 12 11 F o r m a t Binary Binary ASCII ASCII ASCII ASCII Table 7 2 Number of Bytes in Various Replies Two command examples for calculating the digital transmission times are shown below These examples are for 9600 baud selection ASCII Message of Characters Transmission Time Inquiry 23P1 cr Reply 23CP 16 437 cr ...

Page 85: ...8 SPECIFICATIONS ...

Page 86: ...9 group addresses multicast 1 global address broadcast 1 null address address not assigned Bus Operating Modes Response to a designated unit request Sequential response to selected units request Sequential response by all units to a single request Continuous response by any or all for RS 232 units Pressure Units Analog or Digital psi mbar bar kPa MPa in Hg mm Hg torr in wc ft wc m wc cm wc kg cm2 ...

Page 87: ...PPT Plastic Connector PPT Metal Connector PPTR Signal Name 1 A RS 232 TD or RS 485 B 2 B RS 232 RD or RS 485 A 3 C Case Ground 4 D Common Ground GND 5 E DC Power In 6 F Voltage Output Figure 9 1 PPT Case Outline Figure 9 2 Electrical Connector ...

Page 88: ...9 50 51 52 53 54 55 56 57 58 59 P Q R S T U V W X Y 112 70 113 71 114 72 115 73 116 74 117 75 118 76 119 77 120 78 121 79 p q r s t u v w x y 26 27 28 29 30 1A SUB ctrl Z 1B ESC ctrl 1C FS ctrl 1D GS ctrl 1E RS ctrl 58 3A 59 3B 60 3C 61 3D 62 3E 90 91 92 93 94 5A Z 5B 5C 5D 5E 122 7A z 123 7B 124 7C 125 7D 126 7E 31 1F US ctrl _ 63 3F 95 5F _ 127 7F DEL Table 9 2 RS 232 Standard Pin Connections 82...

Page 89: ... photocopying and recording for any purpose without the express written permission of Honeywell Inc Honeywell reserves the right to make changes to any products or technology herein to improve reliability function or design Honeywell does not assume any liability arising out of the application or use of any product or circuit described herein neither does it convey any license under its patent rig...

Page 90: ...Honeywell Aerospace 12001 State Highway 55 Plymouth MN 55441 www honeywell com ...

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