background image

CI-9110 5-3  Service

 

5.3  SETTING OUTPUT LIMITS

 

 

5.3.1  General Principles

 

 
The Regulator provides mechanical output limits that prevent the output from 
underranging or overranging the process. When the Command Input is of a value that 
causes the stepper motor to drive against a limit, the clutch will allow the driveshaft to slip. 
After the motor has completed several revolutions, the software will turn it OFF to prevent 
clutch wear. The motor will remain OFF until the Command Input signal returns to a value 
that is within the set limits. 
 

5.3.2  Test Setup

 

 
When a Remote Set Regulator leaves the factory, the low limit is set to about -10% below 
the minimum range value, and +10% above the high range value. These limits may be 
changed in the field if the user has the capability to adjust the dc input signal over the full 
range of the Regulator and to monitor the pressure output. Bench calibration setups similar 
to that shown in Figures 5-2 or 5-3 may be used to set the mechanical limits on Analog or 
Raise/Lower models. The DMMs (digital multimeters) shown in both illustrations are not 
required for setting limits. 
 

5.3.3  Procedure

 

 
The method of setting the mechanical Hi and Lo Limit adjustments are described as 
follows: 
 
1.  Check that pressure supply to Remote Set Regulator is at proper value. Turn off dc 

power source (12 or 24 V dc) to Remote Set Regulator and remove Regulator Cover.  

 
2.  For all models, set switch SW2-6 to CLOSE to disable  the Guard input. 
  
3.  For Analog models, set jumpers W1 and W2 for Fail/Hold mode. See Section 3, Board 

Setup. Turn ON dc power source.  

 
4.  Locate two limit adjustment tangs on main gear assembly. Refer to Figure 5-1. 
 
5.  Adjust dc test input level to approximately -20% below minimum range value. Pressure 

output will fall to a minimum value and remain there. 

 
6.  If limit tangs were previously set at factory their positions on main gear will appear 

about as shown in Figure 5-1. If tangs are at different positions, other limit values may 
have been field-selected. 

 
7.  Turn off dc power. Limits are set by estimating positions on main gear assembly. To set 

a limit, slightly lift edge of tang from teeth of main gear and carefully move tang to ap-
proximate desired position. Release tang to lock its position. If access to a tang is 
blocked, re-apply dc power and adjust dc input level to a value that will rotate main 
gear in a direction to make tang accessible. Turn off dc power and set limits as required. 

 
 

Summary of Contents for Bristol 9110-00A

Page 1: ...www EmersonProcess com Bristol Instruction Manual CI 9110 Mar 2007 Series 9110 Remote Set Regulator Model 9110 00A ...

Page 2: ...to Bristol for repairs or evaluation please note the following The party sending such materials is responsible to ensure that the materials returned to Bristol are clean to safe levels as such levels are defined and or determined by applicable federal state and or local law regulations or codes Such party agrees to indemnify Bristol and save Bristol harmless from any liability or damage which Bris...

Page 3: ...XTEND BEYOND THE DESCRIPTION OF THE FACE HEREOF F No agent of Bristol is authorized to assume any liability for it or to make any written or oral warranties beyond those set forth herein REMEDIES A Buyer s sole remedy for breach of any warranty is limited exclusively to repair or replacement without cost to Buyer of any goods or parts found by Seller to be defective if Buyer notifies Bristol in wr...

Page 4: ...he Bristol Web site www bristolbabcock com and sending it via E Mail to brepair bristolbabcock com A Bristol Repair Dept representative will return E Mail or other requested method with a RA number C Mail Mail the form GBU 13 01 to Bristol Inc Repair Dept 1100 Buckingham Street Watertown CT 06795 A Bristol Repair Dept representative will return call or other requested method with a RA number D Pho...

Page 5: ...tach a separate sheet if necessary 2 Comm interface used Standalone RS 485 Ethernet Modem PLM 2W or 4W or SNW Other ______________ 3 What is the Firmware revision _____________________ What is the Software version Part III If checking replaced for any question below check an alternate option if replacement is not available A If product is within the warranty time period but is excluded due to Bris...

Page 6: ...ull schedule of classes conducted by full time professional instructors Classes are offered throughout the year at three locations Houston Orlando and our Watertown CT headquarters By participating in our training your personnel can learn how to install calibrate configure program and maintain any and all Bristol products and realize the full potential of your system For information or to enroll i...

Page 7: ...es Many Bristol software products incorporate help screens In addition the software typically includes a read me release notes file detailing new features in the product as well as other information which was available too late for inclusion in the manual Contacting Bristol Inc Directly Bristol s world headquarters is located at 1100 Buckingham Street Watertown Connecticut 06795 U S A Our main pho...

Page 8: ...com Telephone Support Non Technical Questions Product Orders etc Questions of a non technical nature product orders literature requests price and delivery information etc should be directed to the nearest sales office listed on the rear cover of this manual or to your Bristol authorized sales representative Please call the main Bristol Inc number 860 945 2200 if you are unsure which office covers ...

Page 9: ...ONS 2 2 2 3 1 General Piping 2 2 2 3 2 Moisture in Lines 2 3 2 3 3 Line Size 2 4 2 3 4 Venting 2 4 2 4 INTERNAL ACCESS 2 4 2 4 1 Body and Cover 2 4 2 4 2 Electrical Conduit Port 2 5 2 5 INSTALLATION IN HAZARDOUS LOCATIONS 2 5 Section 3 BOARD SETUP 3 1 USING OPTION SWITCHES 3 1 3 1 1 Switch Functions 3 2 3 2 ANALOG INPUT MODELS 3 2 3 3 RAISE LOWER MODELS 3 2 3 3 1 Continuous Signal 3 3 3 3 2 Increm...

Page 10: ...OR ANALOG MODELS 5 6 5 7 1 Feedback Zero Span 5 6 5 7 2 Current Output Span Load 5 6 5 7 3 Pressure Output Check 5 6 5 8 DETAILED CALIBRATION FOR RAISE LOWER MODEL 5 7 5 8 1 Feedback Zero Span 5 7 5 8 2 Current Output Span Load 5 8 5 9 PCB REFERENCE DRAWINGS 5 8 Section 6 SPECIFICATIONS 6 1 ANALOG INPUT MODEL 6 1 6 2 RAISE LOWER INPUT MODEL 6 1 6 3 GUARD INPUT 6 2 6 4 ANALOG OUTPUT 6 2 6 5 ACCURAC...

Page 11: ...f the cover provides access to the field wiring terminals and the programmable option switches Regulators are factory furnished for 12 Vdc or 24 Vdc supply operation These voltage ratings are fixed and cannot be changed in the field In line or pipe mounting are offered as for installations The former uses a 1 4 inch rigid pressure line for support while the latter includes a special bracket for tw...

Page 12: ...ns of the Remote Set Regulator This circuit analyzes the comparator outputs and sends data to the stepper driver which in turn pulses the stepper motor in either direction Since the driveshaft of the stepper motor is mechanically coupled to the feedback pot and a pressure regulator valve both will be set in accordance with data received from the CPU ...

Page 13: ...CI 9110 1 3 Introduction Figure 1 2 Block Diagram of Analog Type Regulator ...

Page 14: ... The motor requires ap proximately 22 000 steps for full rotation 1 2 2 Guard Input An optional signal can be applied to the guard input to Enable or Inhibit the command Sig nal The guard circuit consists of a non polarized opto isolated circuit whose output is applied to the CPU via a logic circuit Analog Regulator models include a fault detector circuit that is activated through jumper selection...

Page 15: ...CI 9110 1 5 Introduction Figure 1 3 Block Diagram of Raise Lower Type Regulator ...

Page 16: ...uses stepper motor to change the out put by an incremented amount The amount of the output increment is determined by the settings of the configuration switches The outputs of all three opto isolators in Figure 1 3 are status signals that when processed by the CPU establish a pressure output value that corresponds to the input signals The remainder of the circuitry shown in the illustration operat...

Page 17: ...UNTING ARRANGEMENT 1 3 15 psi 1 2 In Pipe Mtg Bracket 2 3 27 psi 2 In Line Pressure Pipe 3 6 30 psi E CERTIFICATION 1 None 2 FM EXP NI 3 CSA EXP NOTE This table is only provided for product identity and not for or dering purposes Contact the Bristol Sales Department for ordering information ...

Page 18: ...BLANK PAGE ...

Page 19: ...ing Refer to the overall dimension of Figure 2 1 for views of the universal pipe mounting bracket For this type of installation the bracket is assembled to the Regulator using three screws Select the desired set of bracket holes for either vertical or horizontal mounting pipes Once the bracket is mounted position the assembly next to the pipe as required and install the u bolts from the hardware k...

Page 20: ...ssure supplies that exceed this value will require an external pressure regulator or limiter Figure 2 1 Overall Mounting Dimensions 2 3 1 General Piping A basic piping diagram is shown in Figure 2 3 The pressure supply line may include a pressure gauge external regulator filter and a shutoff valve as shown Union type connections are recommended for pressure lines to allow an easy disconnect A pres...

Page 21: ...hecks without disturbing other equipment operating on the line Figure 2 2 Regulator Assembly 2 3 2 Moisture in Lines The Regulator should be installed so that the supply and output lines slope downward and away This arrangement allows any condensate trapped in the lines to drain away from the instrument ...

Page 22: ...essure source for a Remote Set Regulator the VENT port must be piped to a safe location Warning Covers of Remote Set Regulators operating in hazardous areas should not be removed If servicing is required the environment should first be made safe or the supply power should be turned off allowing the instrument to be discon nected and removed to a safe area Figure 2 3 Typical Pressure Connections 2 ...

Page 23: ...ea must be enclosed in metal conduit The point where the conduit connection meets the unit s housing should be properly tightened to prevent entry of gas or other ignitable substances Explosion proof wiring practices must be followed to prevent flashback through the conduit B The cover of the installed unit must be screwed in hand tight and fully seated The cover must not be damaged and no threads...

Page 24: ...BLANK PAGE ...

Page 25: ...pen circuit The switch assemblies are fragile and require careful handling Use a small blunt object such as a miniature screwdriver to set the switch positions Do not use pencils ballpoint pens or extremely sharp objects for this purpose WARNING When starting a unit for the first time all switch options must be set before any power is applied Improper switch settings can cause improper operation o...

Page 26: ...SW2 6 Guard Active Inactive 3 5 SW2 7 Not Used None SW2 8 Analog Input V or I 3 2 Record your switch settings ON or OFF here for future reference List your corresponding switch functions or values here 3 2 ANALOG INPUT MODELS Initially it will be necessary to check the position of switches SW1 1 through SW1 5 These switches must be set to their OPEN positions to properly disable the functions asso...

Page 27: ... increment from 0 110 per pulse to 1 830 per pulse The pulses that raise or lower the output perform in real time and are not stored As a requirement each pulse must remain in a TRUE state for a period of time necessary for the Remote Set Regulator to reach the new output value Should the input change from a raise to a lower operation or vice versa before the completion of an incremental step the ...

Page 28: ...pen Close 0 110 Pulse Open Close Close Close Open 0 182 Pulse Open Close Close Open Close 0 365 Pulse Open Close Open Close Close 0 730 Pulse Open Close Open Open Close 1 090 Pulse Open Close Open Open Open 1 280 Pulse Open Open Close Close Close 1 460 Pulse Open Open Close Close Open 1 640 Pulse Open Open Close Open Close 1 830 Pulse Open Open Open Open Open Continuous Analog Regulator models mus...

Page 29: ...rminal is in a TRUE state The dynamic mode which is only available with Raise Lower models responds to the simultaneous transition of two pulse type signals Consequently the output will only change when a guard pulse and a command pulse either a raise or lower occur at the same moment Furthermore both pulses must remain TRUE until the actuator output change is complete If either a guard or command...

Page 30: ...l stop the stepper motor at the last pressure output value prior to the loss of the analog input signal Note that the Guard terminals are not available for external usage in this mode The Fault Detector trip point for this mode is factory set at 0 8 volts which corresponds to 5 of fullscale In the alternate Fail Zero mode the Guard terminals are available for use with an external signal In this mo...

Page 31: ... failure of the AI Command Input signal value fails below 0 causes the pressure output to decay to 0 of scale and remain there until a normal AI is received Should the Guard Input go FALSE prior to the AI command failure the last pressure output value will be held Figure 3 2 Jumper Location on Analog Termination Board ...

Page 32: ...BLANK PAGE ...

Page 33: ...ains the field wiring terminals Access to this board is obtained by removing the cover as described in Section 2 Installation Two terminal blocks TB1 TB2 are located on the termination Board as shown in Figure 4 1 Each of these blocks contain six 6 terminal screws for field wiring connections TB1 contains terminals TB1 1 through TB1 6 while TB2 contains TB2 1 through TB2 6 The function of each ter...

Page 34: ...B1 4 TB1 5 TB1 6 TB2 1 TB2 2 TB2 3 TB2 4 TB2 5 TB2 6 Green Screw Raise Command Input Raise Com Command Input Lower Command Input Lower Com Command Input Guard Guard Com Remote Local Status Current Out Current Out Supply Supply Unused Chassis Note Raise Lower Guard Terminals are non polarized and opto isolated 4 3 ANALOG VOLTAGE INPUT 1 5 V WITH GUARD A voltage signal can be used as the Command Inp...

Page 35: ...CI 9110 4 3 Field Wiring Figure 4 2 Analog Voltage Input with Guard Figure 4 3 Analog Current Input with Guard ...

Page 36: ...l is one that produces a step change of the output value for each TRUE input pulse that is received Both types of inputs will maintain the last output value during the FALSE or failed states of the signal The wiring illustrations described herein are applicable to either type The Guard input performs the same function as described under the previous analog subtopics Since the Guard input is electr...

Page 37: ...CI 9110 4 5 Field Wiring Figure 4 5 Raise Lower Guard Inputs from Relay Contacts Figure 4 5 Raise Lower Guard Inputs from Open Collectors ...

Page 38: ...the loop resistor present at the input of the Analog Transmitter The current signal modulates a tone carrier which communicates with an Analog Tone Receiver at the command site not shown 4 7 DC POWER The Remote set Regulator is factory shipped for 12 or 24 Vdc supply operation Before power is applied a check should be made to ensure that the Regulator type matches the supply source The dc supply s...

Page 39: ... some form of guarded control A process that is not guarded may run out of control and cause property damage and injury to persons Once these conditions have been met proceed as follows 1 The Regulator will be furnished as a 12 or 24 V dc type Make sure that the supply voltage is correct for the Regulator 2 Remote Set Regulators will be furnished with a 3 15 3 27 or 6 30 psig output range Check in...

Page 40: ...ce it as required with a 1A 250V 3AG type If the fuse continues to blow check for wiring mistakes at the field wiring terminals or check for a defective PC board Do not attempt further operation until the problem has been resolved 6 Once all the above checks have been completed turn on the associated process and verify that the Regulator is operating properly Startup is complete ...

Page 41: ...en to close down the process or to isolate the Regulator in such a manner that it has no control over the process Warning Models intended for operation in hazardous areas require additional precautions Under no circumstances should the cover be removed while the instrument is powered and operating If access is required either the dc power must be turned off or the environment must be made safe i e...

Page 42: ...rd is not used make sure SW2 6 is in the CLOSE position Severe output tracking errors on Analog model Check setting of switches SW1 1 5 If any are set to Pulse Increment mode the output will not balance properly These switches must be set OPEN for Analog models Noisy or Erratic Output on Raise Lower Model Try SW1 8 in both positions and choose the one with the lowest noise level For Analog models ...

Page 43: ...ts 5 3 3 Procedure The method of setting the mechanical Hi and Lo Limit adjustments are described as follows 1 Check that pressure supply to Remote Set Regulator is at proper value Turn off dc power source 12 or 24 V dc to Remote Set Regulator and remove Regulator Cover 2 For all models set switch SW2 6 to CLOSE to disable the Guard input 3 For Analog models set jumpers W1 and W2 for Fail Hold mod...

Page 44: ...Raise Lower model uses a switch test circuit con sisting of two pushbutton switches that apply dc power to either the Raise or Lower inputs As long as a switch is pressed the output will be raised or lowered assuming continuous dc input configuration From this point on the test setups of Figures 5 2 and 5 3 are identical A digital multimeter DMM 1 is connected across test points TP3 and TP4 to mon...

Page 45: ...est gauge If range of travel is not complete mechanical limits are less than output span or 0 Limits 100 At this time position limits to following settings see topic 5 3 Lo Limit 10 approximately Hi Limit 110 approximately If full range cannot be obtained even with above limits other problems may be indicated Refer to topic 5 2 for troubleshooting hints before proceeding Figure 5 2 Analog Test Set...

Page 46: ...5 000 V 5 DMM 1 should read 4 995 V 004 V 6 If the reading of step 5 is out of tolerance adjust potentiometer R35 on CPU to correct 7 Recheck both points and readjust zero and span if required 5 7 2 Current Output Span Load The current output circuitry is provided with two calibration adjustments Potentiometer R50 is used for span adjustment and R49 for load compensation For these tests DMM 2 used...

Page 47: ...ODEL If calibration errors were found using the procedures of topic 5 6 the procedures described herein for Raise Lower models are performed 5 8 1 Feedback Zero Span The tracking voltage provided by the motor driven feedback potentiometer is calibrated against the pressure output as follows 1 Adjust input test circuit for minimum range indication on test gauge 3 or 6 psi 2 DMM 1 should read 0 995 ...

Page 48: ...ding increases adjust R49 CCW If reading decreases turn it CW Repeat procedure until change is less than 02 mA 4 Final reading should be 20 mA 02 mA If necessary reset pot R50 and repeat procedure 5 Calibration is complete Restore unit to normal operating status 5 9 PCB REFERENCE DRAWINGS Table 5 1 below provides part numbers and drawing references Figures 5 4 through 5 7 for the printed circuit b...

Page 49: ...CI 9110 5 9 Service Figure 5 4 Assembly Analog Type CPU Board with Current Output Figure 5 5 Assembly Analog Termination Board ...

Page 50: ...Service 5 10 CI 9110 Figure 5 6 Assembly Raise Lower Type CPU Board with Current Output Figure 5 7 Assembly Raise Lower Termination Board ...

Page 51: ...ated and bi polar Limited to 47 V by metal oxide varistor MOV Types of Inputs Accepted May be configured for continuous dc input signal On or Off or dc pulse incrementing signal Continuous DC Input Maximum dc input level is a function of the supply voltage as follows 12V Model 11 14 Vdc 24V Model 22 28 Vdc DC Pulse Incrementing Input Pulse rates adjustable from 0 110 pulse to 1 830 pulse Pulse mus...

Page 52: ... 5 of span Pressure output to Feedback 5 of span 6 6 ACCURACY RAISE LOWER MODELS Feedback Volts to Pressure Output 5 of span Pulse Input to Pressure Output 20 of span 6 7 DC POWER 12 Volt Model 11 14 Vdc 0 35 A Max 24 Volt Model 22 28 Vdc 0 25 A Max Fuse 1 A 250 Vdc 3AG 6 8 STEPPER DRIVE MECHANISM Stepper Motor Gearing from motor shaft to pressure regulator assembly results in approximately 22 000...

Page 53: ...Supply Pressure Range Type Min Max Unit Supply Supply psig psig psig 3 15 20 100 3 27 30 100 6 30 35 100 Supply Pressure Effect 0 1 psig Max change in output for each 10 psig change of input Connection IN OUT and VENT ports 1 4 Inch NPT 6 10 INSTRUMENT ENCLOSURE Type of Case Weatherproof and explosion proof Cast aluminum with gasketed screw on cover Gray epoxy finish Meets NEMA 3 specifications Ge...

Page 54: ...er 20 to 130 F 29 to 55 C range 10 to 50 over 130 to 150 F 55 to 65 C range Vibration Limits 0 1 gram Max over 10 to 500 Hz range RFI Rejection Per SAMA standard PMC 33 1 Class 1 and 2 20 MHz to 500 MHz Rejection is greater than 0 5 full scale error ...

Page 55: ...01 7 16 Motor Assembly 12 V dc type 390738 01 8 24 V dc type 390738 02 6 17 Bracket Terminal Block 390080 01 2 18 Clamp Pot 390090 01 8 19 PC Board Assembly 624 II Remote Raise Lower Termination Board 12 24 Vdc Discrete Input Versions 389616 01 0 12 24 Vdc Analog Input Version 389644 01 3 20 Gear 68 Teeth 64 Pitch 390735 01 9 21 Jumper Remote Regulator 390761 01 0 23 Screw 4 40 x 3 1 Pan Head 3746...

Page 56: ...Parts 7 2 CI 9111 Figure 7 1 Remote Set Regulator Actuator Unit ...

Page 57: ...864 ID x 070 W 317303 08 2 102 Seat Spring 396404 01 4 104 Plug N P T Hex Socket 379891 05 0 115 Bushing Regulator Shaft 396403 01 8 251 Regulator 390737 252 Spring 3 15 psig Range 390737 01 1 Spring 3 27 6 30 psig Range 390737 02 0 Parts Referenced in Figure 7 2 Item Description Part Number 103 Screw 10 32 x 1 1 2 SHCS 396400 02 7 201 Bracket Mounting 390190 01 2 202 Screw 1 4 20 x 1 2 Hex Head 3...

Page 58: ...ase Pressure Regulator Ass y 342172 00 0 106 Spring Helical Compression 307905 00 4 107 Screw 10 32 x 1 SHCS 396400 01 9 108 Screw 7 16 x 20 Pilot Retaining 297261 00 2 110 Plunger Regulator 307908 00 3 111 Diaphragm Ass y Exhaust 396394 01 9 112 Spacer 297248 00 6 113 Block Regulator 390570 01 0 116 Diaphragm Regulator 385268 01 7 Figure 7 3 Remote Set Regulator Assembly Basic Parts ...

Page 59: ...s are unmanned and located in remote areas failures resulting from an improperly grounded system can become costly in terms of lost time A properly grounded system will help to prevent electrical shock hazards resulting from contact with live metal surfaces protect equipment from lightning strikes and power surges minimize the effects of electrical noise and power transients and reduce signal erro...

Page 60: ...RADIUS AT LEAST 12 STRANDED COPPER CABLE AWG 0000 PROTECTION BOX CLAMP ONE PER CONDUCTOR 1 PROTECTION BOX COMMUNICATIONS GROUND GROUND RODS PER N E C GROUND BED AWG 0000 COPPER PERIMETER FENCE POWER GROUND TESTED EARTH CONNECTION STRANDED COPPER CABLE AWG 0000 METER TUBES INSTRUMENT HOUSE RTD WELLS METER STAND Figure 1 Basic Ground Rod Installation Figure 2 Overhead Map of Ground Bed for Gas Meter...

Page 61: ...h several grounding options The user should refer to the instrument manual and follow grounding recom mendations o Common Returns The use of a single common return wire for two or more input signals is not recommended This approach may introduce system ground loops that cause erroneous readings at the instrument Shielded transmitter or sensor wires should be grounded at the input of the instrument...

Page 62: ... AWG 10 COPPER WIRE SMOOTHLY DRESSED AT DEMARKATION POINT INSTALL COMMUNICATIONS LIGHTNING ARRESTER S ON POLE OR OUTSIDE OF BUILDING COMMUNICATIONS GROUND ROD CLAMP OR BRAZE RADIUS 12 IN GROUND BED CONDUCTOR STRANDED COPPER CABLE AWG 0000 PHONE LINE S Figure 3 Grounding of Equipment Housing Figure 4 Grounding of Phone Line ...

Page 63: ...ignal interference and provide equipment protection from lightning or transients the earth ground at the site must be tested to insure that its impedance measures less than 10 ohms at 7 MHz This qualification is essential since a transient potential or an interference signal at the instrument site can vary over the entire electromagnetic spectrum from DC to several hundred MHz Note that transients...

Page 64: ...PPER CABLE AWG 0000 TW TWISTED SHIELDED PAIR FOR SIGNAL RADIUS 12 IN GAS DISCHARGE TUBE LIGHTNING ARRESTOR BRAZE CONNECTION CLAMP OR BRAZE THERMOMETER WELL PIPE SUPPORT 1 DIA COPPER BRAID AWG 4 OR LARGER DRESSED TO SMOOTH CURVE METER RUN SOIL LINE GROUND BED STRANDED COPPER CABLE AWG 0000 FOUNDATION Figure 5 Grounding of Transmitter Figure 6 Grounding of Thermometer Well in Gas Line ...

Page 65: ...ocess vats metal piping and other associated mechanical and electrical devices should all be grounded The method of grounding an instrument rack is shown in Figure 3 In this application the ground lead typically attaches to a ground bus that is common to all equipment in the rack For applications employing equipment that communicates over telephone lines a lightning arrestor must be provided at th...

Page 66: ...S1400 POWER COMPANY GROUND AND GROUND ROD SERVICE TRANSFORMER GROUND BED CONDUCTOR TEST POWER COMPANY GROUND ROD LIGHTNING ARRESTERS EACH PHASE NOTE ELECTRIC METER MAIN BREAKER BOX Figure 7 AC Power Grounding System ...

Page 67: ...ound High currents from lightning strikes could also melt sand and cause glass to form around the ground rod making it ineffective A buried counter poise or copper screen is preferred for these installations along with regular applications of salt water Rocky Soil Rocky soil can pose many grounding problems A counterpoise or copper plate will probably be required Constructing a trench at the groun...

Page 68: ...umpers W1A and W1B on the System Interconnect Board must be removed to isolate the chassis connection from the 24VRET connection see Figure 8 If it is a Model 3330 jumpers W1A W1B and W1C on the System Interconnect Board must be removed Series 3308 Gas Flow Computers or Correctors if used with these systems provide an isolated instrument ground without setting jumpers 3 AC Power Source The 24 Vdc ...

Page 69: ...ref See text Conduit Pipe CHASSIS 24VRET W1 DPC 33XX METEL CABINET OR RACK To Zero Ref Point of Facility 4 gauge min LINE CHASSIS 24VRET W1 DPC 33XX 24V NEUTRAL CHASSIS 24V Bonding Strap From Other Units 24VRET 120 Vac 24V Figure 8 Grounding for DPCs and Power Supplies in Single Metal Cabinet ...

Page 70: ... at points specified in the NEC 4 Grounding of Peripheral Equipment Some peripheral devices such as printers CRTs personal computers etc have their internal logic ground connected to the chassis This configuration will cause loss of isolation between the DPC s instrument ground and chassis These devices may still be used providing that opto isolated circuits galvanic isolation or other types of ci...

Page 71: ...ound Cable Trays Bonded To Structure Safety Ground Electrical Supporting Structure Bonded To Building Structure Utility Pipe Bonded To Structure Cable Tray Sections Grounded Equipment Cabinets Bonded To Equipment Ground Plates Or To Structure From Grounding for the Control of EMI by Hugh W Denny see ref 1 Courtesy of Interference Control Technologies Figure 9 Elements of a Facility Ground System ...

Page 72: ...nnect to each other and then to a single wire that connects to the zero reference point of the facility This wire should be 4 gauge minimum multistranded and insulated and be contained in a metal conduit pipe A heavier stranded 4 0 gauge could be used to connect each cluster to the zero reference point while the 4 wire instrument grounds could be locally terminated to the 4 0 wire The conduit cont...

Page 73: ...BLANK PAGE ...

Page 74: ...ectric Co Other trademarks or copyrighted products mentioned in this document are for information only and belong to their respective companies or trademark holders Copyright c 2006 Bristol Inc 1100 Buckingham St Watertown CT 06795 No part of this manual may be reproduced in any form without the express written permission of Bristol Inc Emerson Process Management Bristol Inc 1100 Buckingham Street...

Reviews: