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(4) Status information BFM #29

(5) Identification code BFM #30

The identification (or ID) code number for a Special Function Block is read using the FROM command.

The code for the FX-4AD unit is K2010.

The user's program in the PC can use this facility in the program to identify the special function block
before commencing data transfer from and to the special function block.

CAUTION

Values of BFM #0, #23 and #24 are copied to EEPROM memory of the FX-4AD. BFM #21 and

BFM #22 are only copied when data is written to the gain/offset command buffer BFM #22. Also,
BFM #20 causes writing to the EEPROM memory. The EEPROM has a life of about 10,000 cycles
(changes), so do not use programs which frequently change these BFMs.

Because of the time needed to write to the EEPROM memory, a delay of 300 ms is required
between instructions that cause a write to the EEPROM.

  Therefore, a delay timer should be used before writing to the EEPROM a second time.

NOTE : • b4 to b7,b9 and b13 to b15 are undefined.

Bit

ON

OFF

b  0:Error

When any of b1 to b4 is ON.

If any of b2 to b4 is ON,A/D conversion

of all the channels is stopped

No error

b  1:Offset/Gain error

Offset/Gain data in EEPROM is corrupted

or adjustment error.

Offset/Gain data normal

b  2:Power source abnormality

DC 24V power supply failure

Power supply normal

b  3:Hardware error

A/D converter or other hardware failure

Hardware normal

b  8:Not READY

FX-4AD MODE switch is not set to READY

READY mode

b10:Digital range error

Digital output value is less than -2048

or more than +2047

Digital output value is normal

b11:Averaging error

Number of averaging samples is 4097 or

more or 0 or less

(default of 8 will be used)

Averaging is normal (between 1 and 4096)

b12:

Offset/Gain adjust prohibit

Prohibit-(b1,b0) of BFM #21 is set to (1,0)

Permit-(b1,b0) of BFM #21 is set to (0,1)

Summary of Contents for MELSEC-F FX-4AD

Page 1: ...on set Data transfer between the FX 4AD and the FX base unit is by buffer memory exchange There are 32 buffer memories each of 16 bits in the FX 4AD The FX 4AD occupies 8 points of I O on the FX FX2C expansion bus The 8 points can be allocated from either inputs or outputs The FX 4AD draws 30mA from the 5V rail of the FX base unit or powered extension unit This manual contains text diagrams and ex...

Page 2: ...erminals to each other 4 If there is excessive electrical noise connect the FG frame ground terminal with the grounded terminal on the FX 4AD 5 Connect the ground terminal on the FX 4AD unit with the grounded terminal on the base unit Use class 3 grounding on the base unit if available 73 2 87 63 2 48 95 3 74 140 5 51 125 4 92 Mounting holes 5 5mm 0 27in dia Extension cable and connector 10 0 39 M...

Page 3: ...can be selected with your choice of input terminal Up to four input points can be used at one time Analog input range DC 10V to 10V input resistance 200K Ω DC 20mA to 20mA input resistance 250 Ω Warning this unit may be damaged by input voltage in excess of 15V Warning this unit may be damaged by input currents in excess of 32mA Digital output 12 bit conversion stored in 16 bit 2 s complement form...

Page 4: ...n between analog and digital circuits DC DC converter isolation of power from FX base unit No isolation between analog channels Number of occupied I O points 8 points taken from the FX expansion bus can be either inputs or outputs Digital Output 10V 10 235V Voltage Input 2047 2000 10 24V 10V 2000 2048 NOTE Preset ranges are selected by an appropriate setting in buffer memory of the analog block Cu...

Page 5: ...ions BFMs marked with an data can be written from the PC using the TO command For buffer memories BFMs without the mark data can be read to the PC using the FROM command Before reading from the analog special function block ensure these settings have been sent to the analog special function block Otherwise the previous values held in the analog block will be used The buffer memory also gives a fac...

Page 6: ... and offset values of BFM 23 and 24 are sent to non volatile memory gain and offset registers of the specified input channels Input channels to be adjusted are specified by the appropriate G O gain offset bits of BFM 22 Example If bits G1 and O1 are set to 1 input channel 1 will be adjusted when BFM 22 is written to by a TO instruction Channels can be adjusted individually or together with the sam...

Page 7: ...tween instructions that cause a write to the EEPROM Therefore a delay timer should be used before writing to the EEPROM a second time NOTE b4 to b7 b9 and b13 to b15 are undefined Bit ON OFF b 0 Error When any of b1 to b4 is ON If any of b2 to b4 is ON A D conversion of all the channels is stopped No error b 1 Offset Gain error Offset Gain data in EEPROM is corrupted or adjustment error Offset Gai...

Page 8: ...he calibrated line identified at a digital value of 0 d Negative offset e Zero offset default 0V or 4mA Positive offset f Analog Digital Offset value f e d 0 1000 Digital a b c Gain value Analog Offset Gain Offset and gain can be set independently or together Reasonable offset ranges are 5 to 5V or 20mA to 20mA and gain values 1V to 15V or 4mA to 32mA Gain and offset can be adjusted by software in...

Page 9: ...d stored at D4 in the base unit This is compared to check the block is an FX 4AD if OK M1 is turned ON These two program steps are not strictly needed to perform an analog read They are however a useful check and are recommended as good practise The number of averaged samples for CH1 and CH2 is set to 4 by writing 4 to BFM 1 and 2 respectively Do not execute the pulse If there are no errors in the...

Page 10: ...ition of block No 0 i e closest to the FX base unit Example Adjusting gain offset via software settings X010 SET M0 Adjustment start M0 TO P K0 K0 H0000 K1 TO P K0 K1 K1 K21 H0000 BFM 0 initialize input channels Enter the instructions on the left and RUN the PC with the MODE switch of the FX 4AD set to READY K1 BFM 21 BFM 21 gain offset adjust prohibit must be set to permit with b1 b0 0 1 TO K0 K0...

Page 11: ...sion unit varies according the number of extension block or special function blocks connected Put the FX base unit into RUN 6 2 Error checking If the FX 4AD special function block does not seem to operate normally check the following items Check the status of the POWER LED Lit The extension cable is properly connected Otherwise Check the connection of the extension cable Check the external wiring ...

Page 12: ... Electric distributor Under no circumstances will Mitsubishi Electric be liable or responsible for any consequential damage that may arise as a result of the installation or use of this equipment All examples and diagrams shown in this manual are intended only as an aid to understanding the text not to guarantee operation Mitsubishi Electric will accept no responsibility for actual use of the prod...

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