Honeywell RP920A-D Mounting instructions

RP92OD
RP920A-D
Modular Pneumatic
Controller
Service Data
TABLE OF CONTENTS
GENERAL .......................................................................................................................................
3
Description ....................................................................................................................................
3
Application ...................................................................................................................................
3
Specifications ................................................................................................................................
4
Operation......................................................................................................................................
4
RP920A or C Controller..
4
RP920B or D Controller
...............................................................................................................
4
MAINTENANCE..
Equipment Required
........................................................................................................................
4
Inspection and Cleaning
Compensation Startpoint (RP920B and D)
.......................................................................................
...................................................................................................................
5
Operational Check ..........................................................................................................................
5
All Systems
...............................................................................................................................
5
System in Operation
....................................................................................................................
5
System not Operating-Sensors Disconnected
..................................................................................
5
Equipment
..............................................................................................................................
5
Pr0xdLu.e ................................................................................................................................
5
Calibration Check..
6
Operating Point (RP920A and B)
...................................................................................................
6
Operating
Point as Maximum Limit
(RP920C and
D).
.......................................................................
6
S etpoint .................................................................................................................................... 6
Calibration....................................................................................................................................
RP920A. . . . .
7
RP920B
. . . . . .
-7
RP920C and D
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9
Adjustments. . . . . . . . . . .
9
General
. . . . . . . . . . . . . . . . . . . . . . . . .
9
85-0142
Copyright 1993 Honeywell Inc. � All Rights Reserved
MLF C. 6.

TABLE OF CONTENTS (Continued)
Direct to ReverseActing
......““““““.““.““.“““.‘..“‘.““.
11
Negative to Positive Compensation (RP920B and D)
..“.“.“‘.‘.““.“.‘.‘......‘........*...
11
Integral Action Cut-Off and Gage Function (RP92OC and D)
..“‘.“.“....“....t.“‘...
11
Setpoint Adjustment
..““““..““.‘.“““‘.““.‘.‘.““*““.“““.‘..‘...*..tl.
12
Local Setpoint Adjustment
..“““.“‘.“.“‘.““.““““‘.““““““.“““‘.““““.“‘.““‘.‘.‘..“..“..--.‘.
12
Remote Setpoint Adjustment ..““““““““““‘.““‘.‘.“.‘..““.“““‘....“*“‘.““.““..“““..“‘...‘*.‘..‘...“.
12
Control Point Adjustment (CPA Models Only) ..“““..““.““‘...‘n‘..“......‘f...s
13
Proportional Band Adjustment
..,‘.“““‘..“.‘...*..‘..
13
Authority Adjustment (RP920B and D)
...‘.“‘..‘.*‘.“.““‘.“‘..‘.1..‘.‘.*..--...
13
Compensation Startpoint Adjustment (RP920B and D)
..‘.“““..“.‘..“‘*.“.*..
13
Reset Time Adjustment (RP920C and D) ..““.““““..““‘.“““““‘....“‘*‘.‘.‘.‘.‘.““““““..““....“.‘...f..
13
Cover ....*...“‘.‘....““..‘..“.“‘.‘...“..“‘.““.“..“.‘.“‘.““‘..“..‘..““.“.‘...*....“....‘.““..‘.“‘.‘..**.*.......‘...
13
TROUBLESHOOTING
...*“‘...‘..‘.‘..“.‘.‘..“‘.“..“.“...‘
14
REPAIR... . . . . . . . . . . . 14
Module Replacement
..““.“““““...“........‘..“‘.‘
14
Setpoint Knob Replacement
..‘..““““““.“‘..“‘.*“.“‘.‘.‘.“.“.“.“.““‘.‘
14
Filter/O-Ring Replacement in Connector Block Module
....‘..*‘.““‘.‘.“.‘.“....‘.*...“‘
.
15
Gage Seal Replacement
..‘..‘.“.“.‘.“‘.“““...“‘.‘.“‘.“““‘...‘.‘.‘*“.‘.‘....‘.“.“‘..‘....‘.‘..“*‘.X‘.‘.....“.‘.‘..
15
PARTS AND ACCESSORIES
..“.“.“‘.‘.“‘.“.‘.f*“
. 16
Parts List
......““‘*....“‘*“““.“““““‘
16
Accessories ..*“.“...‘.‘.“““‘..“““‘
16
APPENDIX A
..““..“.““.“.“.‘.“
16
850142
ii

GENERAL
DESCRIPTION
The RP920 Modular Pneumatic Controller, in
conjunction with remote sensors, provides Proportional
(P)
or Proportional Plus Integral (p + I) control of temperature,
humidity, pressure, or dewpoint in WAC systems.
APPLICATION
In the mixed air control application (Fig.
l), the primary
sensor modulates the outdoor and return air dampers
LIMIT
CONTROLLER
MIXED AIR CONTROL SYSTEM
through the primary controller
(RP920C) maintaining a
constant mixed air temperature. The limit controller
(RP920A) and limit sensor sets outdoor air intake to a
minimum.
In the hot water converter control application (Fig.
l), the
primary sensor modulates the steam valve on the converter
to maintain the hot water temperature. On CPA models the
hot water temperature can be adjusted remotely using a
gradual switch.
PRIMARY
M
CPA
1
2 4
rCPA
, MODELS ONLY
PRIMARY
SENSOR
IN HWS
4 8 9 OR C
2 3 1 DA
r-l LINE
STEAM TO CONVERTER
SUPPLY
HOT WATER CONVERTER
CONTROL SYSTEM
Fig. 1Typical Single-Input Controller Applications.
In a dual-input control application (Fig.
2), the RP920B
or D provides reset capability. Often, control of a building
is more efficient if the setpoint of the controller is reset to a
different value as a function of some parameter other than
COMPENSATION
SENSOR (OUTDOOR AIR)
VALV
N.O.
Fig, 2. Typical Dual-Input Control System.
the controlled variable, in this system, outdoor air
temperature. To use compensation, a reset schedule must be
set up (Fig. 3).
FULL
FULL COMPENSATION
COMPENSATION START
COMPENSATION SENSOR
WHERE:
LOWEST VALUE OF CONTROLLED VARIABLE.
HIGHEST VALUE OF CONTROLLED VARIABLE.
VALUE OF COMPENSATION VARIABLE WHEN
CONTROLLED VARIABLE IS AT ITS LOWEST VALUE.
VALUE OF COMPENSATION VARIABLE WHEN
CONTROLLED VARIABLE IS AT ITS VALUE.
21365-l
Fig. 3. Compensation Reset Schedule.
3
85-O 142

SPECIFICATIONS
Models:
RP920A: Single-Input Controller
RP920B: Dual-Input Controller
RP920C: Single-Input P + I Controller
RP920D: Dual-Input P + I Controller
Main Air Supply:
18 psi (124 kPa)
Minimum Air Pressure:
15 psi (103 kPa) minimum
Maximum Safe Air Pressure:
30 psi (207 kPa)
Input Signal:
3 to 15 psi (21 to 103 kPa)
Output Signal:
3 to 13 psi (21 to 90 kPa)
Air Consumption:
and C: 0.021
scfm (9.9 ml/s)
RP920B
and D: 0.046
scfm (21.7 ml/s)
Sensor:
0.019 scfm (9.0 ml/s) depending on
sensor selected
Air Capacity:
0.07 scfm (33.0 ml/s) at 18 psi (124kPa) with 1 psi (7 kPa)
pressure difference
Proportional Band:
2.5 to 50%, field adjustable
Authority (RP920B and D Only):
5 to 300% of primary sensor span
Compensation Start Point (RP920B and D Only):
0 to 100% of compensation sensor span
Integral Reset Time (RP920C and D Only):
0.5 to 20 minutes, field adjustable
Ambient Temperature:
40 to 130F (5 to 55C)
OPERATION
RP920A OR C CONTROLLER
In the mixed air control system with high limit (Fig. 1),
the primary controller modulates the outdoor and return air
damper to maintain the mixed air temperature set on the
controller. As the outdoor temperature rises through the
narrow throttling range of the limit controller, the dampers
are gradually returned to the minimum position as set on the
minimum position switch. When the fan is off, the dampers
assume the normal positions.
In the hot water converter control system (Fig. l), the
primary sensor in the hot water supply from the converter
modulates the steam valve on the steam supply to the
converter to maintain the hot water temperature. As the
water temperature rises through the throttling range the
valve moves from open to closed. If the CPA is used, it can
change the control point temperature percent x the
sensor span.
RP920B OR D CONTROLLER
In the dual-input control system
(Fig. 2), the setpoint of
the primary sensor, located in the discharge air, is reset by
the compensation sensor in the outdoor air. Adjustments are
made on the controller to change the discharge air tempera-
ture according to a predetermined compensation reset
schedule (Fig. 3). The RP920D provides finer control in this
application because of the integral action.
MAINTENANCE
EQUIPMENT REQUIRED
1. Gage 305965 (0- to 30-psi).
2.
Gage Adaptor 729 with plug-in fittings.
3.
Receiver Gage to match primary sensor (see Pneu-
matic Indication, Receiver, and Target Gages Specifi-
cation Data 77-6091).
4. Barb Fitting 14003755-001 (integral models).
5. Controller Calibration Kit MQP8 16A,
6.
Pneumatic Calibration Kit
85-0142

INSPECTION AND CLEANING
Occasionally, check for leaks and loose fittings and
screws. Especially check the self-tapping screw in Port 8
and the self-tapping screw at the top of the integral module
(RP920C and D).
NOTE: Once removed, self-tapping screws can be a
source of air leakage because of a damaged
0-
ring. Check the O-ring and replace it if it is
damaged,
Use a soft cloth or brush to remove accumulated dust and/
or dirt from th eRP920.
OPERATIONAL CHECK
ALL SYSTEMS
Be certain all adjustment settings and conditions are
correct. See job drawing s for prope r settings. Table 1 is a list
of the adjustments available on each model.
Table 1 .RP92 0Adjustments.
of the throttling range as set by the authority and
compensation startpoint. If a discrepancy exists,
recalibrate the controller.
4.
Move th e setpoin tslightly up and down. The BLP
should change proportionally in the same direction
for direct acting and in the opposite direction for
reverse acting controllers. Repeat this step using the
CPA if applicable. If the BLP responds properly, the
controller is good. Return th esetpoin tand CPA to the
original settings,
NOTE: The
RP920C or D should maintai ncontrol
closer to th esetpoin tor reset schedule than
the RP920 Aor B because of the integral
action.
SYSTEM NOT OPERATING-SENSORS
DISCONNECTED
EQUIPMENT
0- to pressure gage.
Restricted air supply, adjustable from 3 to 15 psi (21
to 10 3
kPa) , with receiver gage to match sensors or
Sensor Controller Calibration Ki tMQP816A.
Pneumatic Calibration Kit MQP80 0(optional).
Model
Adjustment X X X X
Proportional Band
X X X X
Internal restrictor
switch
X I Xl X I X
Direct/reverse acting
(proportional
module position)
X X X X
PROCEDURE
1.
Connect the 0- t o30-psi gage to Port 2 (branch).
2.
Connect the main air supply to Port 1 (18 psi
minimum). kPa )adjustable air3
supply with a receiver gage which matches the
I I I
3.
Pipe a 3 to 15 psi (21 to 10
Authority
primary sensor to Port 3.
X
4.
3kPa )adjustable
air supply with a receiver gage which matches the
compensation sensor to Port 5 of an or D.
5. If checking a CPA model, pipe 9 psi to (62 to
Port 9. The or can be used to
Pipe a second 3 to 15 psi (21 to 10
Positive/negative
compensation (switch
block module position
X X
Reset time
X X
Gage/integral cut-off
supply 9 psi (62
(switch block gasket
6.
On an and D, remove and save the seal
screw from the integral module (Fig. 12) and install
Barb Fitting 14003755-001 in its place. Apply 8 psi
SYSTEM IN OPERATION (55 to the integral module. This prevents
integral action. Without this procedure, it is
Be certain th e
HVAC equipment is functional. necessary to allow additional time for the controller
Observe BLP. If it is not between 3 and 13 psi (21 to to finish responding to any change in input pressure
90 kPa) ,slowly adjust th esetpoin tknob and/or CPA or settings.
0kPa )range.until the BLP is in the 3 to 13 psi (21 to 9
and
Allow the system to stabilize before continuing.
a.
Adjust the input air pressure to Por 3t to
Measure the temperature, humidity, or static pressure correspond with the mid-point of the throttling
at the main sensor. This should agree with th e setpoint range of the primary sensor (see APPENDIX
of the throttling range . For theRP920B and D the A).
measurement should agree with the reset schedule
5 85-O 142

b. Set the setpoint knob to the percent of span,
temperature, or humidity that corresponds to the
input pressure. The BLP should be 8 psi (55
kPa). If it is not correct, go to Step 10.
8. RP920B and D:
a.
Plot the reset schedule to determine the
corresponding compensation and primary
sensor values.
b.
Convert the reset schedule value to pressure
(See APPENDIX A) and adjust the air supplies
to those pressures. For an RP920D, the BLP
should be 8 psi (55 kPa). For an RP920B, the
expected BLP depends on which point on the
reset schedule is being simulated. If BLP is not
within 1 psi of the control point pressure, go to
Step 10. Exact control point pressure can be
established for each application by constructing
a chart similar to that shown in Figure 4 and
referencing APPENDIX A. If it is not correct, go
to Step 10.
9. a,
Move the
setpoint knob until the BLP is 8 psi (55
kPa).
Slowly increase the setpoint adjustment
one division The BLP should decrease
proportionally if the controller is direct acting or
increase proportionally if the controller is
reverse acting.
b,
Slowly decrease the setpoint one division. The
BLP should change proportionally in the
opposite direction of Step 9a,
c.
For CPA models, repeat Steps 9a and 9b
substituting the CPA knob for the setpoint knob.
d.
If the controller works properly, go to Step 11. If
the controller works properly, but is out of
calibration, go to Step 10.
To calibrate the controller:
a. Adjust the setpoint knob until the correct BLP is
indicated on the gage.
b. Remove the setpoint knob. Replace it at the
correct setting without changing the
BLP
Return to Step 9.
11.
Connect the tubing and make settings according to
the job drawings.
NOTE: On the RP920C and D, replace fitting in the
integral module with the seal screw. Be sure the O-
ring is sealed
EXAMPLE:
The hot water temperature is reset from 100 to 200F as the
outdoor temperature goes from 60 to -l0F. The range of
the primary sensor is 40 to 240F and the compensation
sensor is -40 to 16OF, Additional settings taken from the
job drawings are:
Compensation startpoint = 60F (or 50 percent).
Compensation is negative.
Authority setting
= 157 percent.
Throttling range =
Proportional Band = 5 percent.
Setpoint = 1OOF (or 30 percent).
180
160
k-z-
@ 140
100
13 PSI (90
THROTTLING RANGE
3 PSI (21
-10 0 10 60 70
OUTDOOR AIR TEMPERATURE
(COMPENSATION SENSOR)
DIRECT ACTING
(21 TO 90 RANGE
220
200
180
140
13 PSI (90
I
100
THROTTLING RANGE
3 PSI (21
-10 0 20 30 40 50 60 70
OUTDOOR AIR TEMPERATURE
(COMPENSATION SENSOR)
DIRECT ACTING
TO 13-PSI (21 TO 90 THROTTLING RANGE c3337
Fig. 4. and D Reset Schedule,
Select (Fig. 4) any compensation sensor value (outdoor
temperature) within the compensation range, in this case
32F. Construct a line vertically to the control point line and
then horizontally to the left side. The hot water temperature
must be 140F to meet the reset schedule.
From APPENDIX A the input pressures are:
Port 3 (primary) 9 psi (62
Port 5 (compensation) = 7.3 psi (50.3 kPa).
The BLP should be 8 psi (55 kPa) for RP920D, or 9 psi (62
kPa)
for RP920B
NOTE:
Previous discussion and illustration assumes 3 to
13 psi (21 to 90
kPa) operating range. However,
the controller may be calibrated to match the
spring range of the actuator (e.g., 4 to 11 psi). The
expected BLP at the would then be the
center of the actuator spring range (e.g., 7.5 psi).
6

CALIBRATION CHECK
TheRP920 is factory calibrated. If the controller does not
operate properly, check the calibration as follows,
OPERATING POINT (RP920A AND B)
1. Pipe the connections (Fig. 5). Install Barb Fitting
14003755-001 in Port 8.
2.
Set the internal restriction to the blocked position.
Adjust the setpoint knob to 50 percent. On the
RP920B, adjust the compensation startpoint knob to
30 percent and set to negative compensation.
3.
Adjust the proportional band to 50 percent and set for
direct acting.
4.
If the BLP is 8 psi (55 kPa), go to Step 5. If not, remove
the setpoint knob (Fig. 6) and turn the operating point
screw with a 5/64-inch Allen wrench until this value
is matched,
5.
Reinstall the self-tapping screw in Port 8.
Fig. 5. Connections for Operating Point Check-RP920A
and B.
OPERATING POINT SCREW
MODULE
KNOB
Fig. 6. Operating Point Screw Location.
OPERATING POINT AS MAXIMUM LIMIT
(RP920C and D)
1. Pipe the connections (Fig. 7). Install Barb Fitting
14003755-001 in Port 8 and in the top of the integral
module. Connect the mainline to the integral module.
This procedure requires 20 psi (138
kPa) minimum
MLP_
2. Adjust the setpoint to 50 percent. On the RP920D
adjust the compensation module to negative compen-
sation and set the compensation startpoint to 30 per-
cent.
3. Adjust the proportional module to direct acting and
set the proportional band to 50 percent.
4.
Adjust the reset time to 15 minutes.
5.
If the BLP is 17.5 psi (120 kPa), go to Step 6. If not,
remove the setpoint knob and turn the operating point
screw with a 5/64-inch Allen wrench until this value
is matched.
6.
Reinstall the self-tapping screws in Port 8 and in the
top of the integral module.
Fig. 7. Connections for Operating Point Check (RP920C
and
SETPOINT
1.
Pipe the connections (Fig. 8). Install Barb Fitting
14003755-001 in Port 8.
2.
Apply MLP.
3.
Adjust the setpoint knob or screw until the gage
reading is 9 psi (62 kPa).
4,
The setpoint knob setting should be 50 percent. If
not, remove the setpoint knob and replace it oriented
to 50 percent.
5.
Reinstall the self tapping screw in Port 8.
85-0142

4 8 9 489 7
23
2 3 1
009 C, AND D
ONLY
8. Connections for RP920 Setpoint Check.
COMPENSATION STARTPOINT (RP920B and D)
1. Pipe the connections (Fig. 9).
2.
Apply
MLP-
3.
Adjust the startpoint knob or screw until the gage
indicates 9 psi (62
kPa).
4.
The setpoint knob setting should be 50 percent. If
not, remove the
setpoint knob and replace it oriented
to 50 percent.
Fig. 9. Connections for RP920B and D Compensation
Startpoint Check.
CALIBRATION
NOTE: The following procedures can be used to calibrate
the RP920, or the MQP816A Controller
Calibration Kit can be used following procedures
in CCT816B Calibration Unit Installation
Instructions 95-7 153
RP920A
If none exists, install a temporary receiver gage
(matching sensor) or a 0- to 30-psi gage in the
primary sensor gage port.
2. Apply MLP.
3.
Install a 0- to 30-psi gage in the BLP test tap.
4. Adjust the setpoint knob until the BLP equals the
centerpoint of the controlled device spring range.
5.
If the setpoint and primary sensor gage do not match,
remove the
setpoint knob and replace it so the setpoint
matches the actual primary sensor gage reading.
6. Readjust the
setpoint to the desired setpoint.
7.
Calibration is complete.
RP920B
Supply the adjustable restricted air (equivalent to
Controller Calibration Kit MQP816A) to Port 3
(primary sensor).
NOTE: Sensors are not connected.
Pipe a receiver gage matching the compensation
sensor, or a 0- to 30-psi gage to Port 5 of the
RP920B.
NOTE: If the controller switch block module
gasket is in Position C, block Port 5 and
use the existing gage.
If a BLP gage does exist, install a 0- to 30-psi gage
in the branch line or in the BLP gage port if the
switch block gasket is in Position B.
4.
Apply MLP.
5.
Adjust the compensation startpoint knob until the
receiver gage indicates pressure equivalent of the
compensation startpoint (Fig. 10 and 11).
NOTE:
Use APPENDIX A to find the equivalent
pressures for the temperature, humidity,
and percent of sensor span.
-THROTTLING
SENSOR
COMPENSATION
START POINT (WC)
Fig. Negative (Winter) Compensation Calibration
Reset Schedule, Direct Acting Controller-3 to 13 psi
Throttling Range.
85-0142
8

PRIMARY
SENSOR THROTTLING
RANGE
COMPENSATION
SENSOR
COMPENSATION
START POINT (WC)
Fig. 11. Positive (Summer) Compensation Calibration
Reset Schedule, Direct Acting Controller-3 to 13 psi
(21 to 90 kPa) Throttling Range.
6.
Adjust the restrictor for the equivalent pressure of
the primary sensor at the compensation
startpoint
on the reset schedule.
7.
Adjust the
setpoint knob until the BLP equals the
desired BLP at the compensation start conditions
(e.g., 13 psi [90 kPa] for negative compensation, 3
psi for positive compensation).
8. If needed, remove the setpoint knob and reposition
it so the
setpoint matches the primary sensor value
at the compensation start. The setpoint knob is
calibrated.
Supply the adjustable restricted air (equivalent to
Controller Calibration Kit MQP816A) to Port 5
(compensation sensor).
10.
Adjust the
restrictors for the equivalent pressure of
the sensors at full compensation on the schedule.
11.
Adjust the authority knob until the BLP equals the
desired pressure of the controlled device with full
compensation conditions.
NOTE: This point can be slightly different from
the calculated authority set on the control-
ler. Leave the new setting on the
controlIer
and mark the job drawings with the new
value.
12.
Calibration is complete.
RP920C AND D
1. Remove and save the screw from the RP92OC or D
integral module (Fig. 12) and install Barb Fitting
14003755-001 in its place.
2.
Apply 8 psi (55 kPa) to the integral module.
3.
Calibrate the
RP92OC following the procedures for
the RP920A. Calibrate the RP920D following the
procedures for the RP920B.
4.
When calibration is complete, remove the barb fitting
and replace screw. Be certain that the O-ring is tight.
REMOVE SEAL
SCREW AND
INSTALL BARB
FITTING.
Fig.
ADJUSTMENTS
GENERAL
1. Some adjustments on the RP920 Modular Pneumatic
Controllers require removal of modules. Module and
port locations are shown in Figures 13 and 14.
2. If a connection to Port 4, 6, or 7 is required, remove the
self-tapping screw from Port 8 and use the screw to tap
the port.
3.
Install Barb Fitting 14003755-001 and O-ring finger-
tight in the appropriate port.
4.
If Port 8 is not used, reinstall the screw.
9 85-0142

I-MAIN I-MAIN
P-BRANCH
E-BRANCH 3-SENSOR
4-VENT
3-SENSOR VENT
B-CLOSED
GAGE
BLOCK
MODULE
PLUG
BRANCH GAGE
PORT
NTEGRAL
MODULE
MODULE
PROPORTIONAL PROPORTIONAL
MODULE MODULE
I-MAIN I-MAIN
2-BRANCH
‘J-PRIMARY 3-PRIMARY
SENSOR SENSOR
VENT VENT
SENSOR SENSOR
&CLOSED &CLOSED
SWITCH SWITCH
BLOCK BLOCK
MODULE
COMPENSATION
SENSOR OR
BRANCH GAGE
G
BRANCHGAGE
PORT
NTEGRAL
MODULE
COMPENSATION
‘ION
PROPORTIONAL
MODULE
I
RP920
Fig. 13. Module and Port Locations.
10

ADJUSTMENT
COMPENSATION
PROPORTIONA
ADJUSTMENT
Fig. 14. Adjustment Locations.
DIRECT TO REVERSE ACTING
1.
Loosen the four screws (Fig. 15) on the proportional
module.
2.
Remove the module. Rotate the module and its gasket
180 degrees and reinstall. Ensure that the notch on the
module lines up with the
proper indication on the
base.
3.
Retighten the four screws.
4.
If required, recalibrate.
PROPORTIONALMODULE
CAPTIVE SCREWS
DIRECT REVERSE ACTING
NOTE LOCATION
0 F NOTCH
Fig. 15. Changing Controller Action
NEGATIVE TO POSITIVE COMPENSATION
(RP920B and D)
Positive compensation is used for summer compensation
or humidity reset applications.
Loosen the four screws on the compensation module
(Fig. 16).
Remove the module. Rotate the module and its gasket
180 degrees and reinstall. Ensure that the notch on the
module lines up with the proper indication on the
base.
Retighten the four screws.
If required, recalibrate.
COMPENSATION MODULE
CAPTIVE SCREWS (4)
NEGATIVE COMP. POSITIVE COMP.
(FACTORY SET) 7 ’
NOTE LOCATION
OF NOTCH.
Fig. 16. Changing from Negative to Positive
Compensation,
lNTEGRAl_ ACTION CUT-OFF AND GAGE FUNC-
TION
(RP920C and D)
1. Check the position of the gasket tab (Fig. 17). The
position of the gasket located under the switch block
module determines the function of the field-installed
gage on the switch block module and determines if the
integral action cut-off function is enabled or disabled,
See Table 2 for factory and field settings.
Table
2. Switch Block Module Gasket Position.
RP920B B C
RP920C B
RP920D
B
C,
B = Branch Line Gage
C = Compensation Sensor Gage
= Action Cut-Off
Enabled
11
85-O 142

Loosen the three screws securing the switch block
module and remove the module. Remove the gasket
and note the symbols embossed on the back of the
module (Fig 17).
3. Rotate and/or flip the gasket until the gasket position
matches the functions desired with the desired letter
showing from the back of the module.
4.
Reinstall the switch block module and tighten the
three screws.
5.
Connect the integral action cut-off switching
components in Ports 6 and 7, if used
BLOCK MODULE
GASKET
TAB
POSITION
F-RON-T-
GASKET SHOWN IN C POSITION. AND ARE ALSO
SHOWN HERE FOR LOCATION.
Fig. 17. Integral Action Cut-Off and Gage Function
Gasket Position
SETPOINT ADJUSTMENT
1. The setpoint knob Fig 18) is embossed with a O-
to loo-percent scale. Scaleplate overlays are included
to match various sensor ranges.
2. Three methods of setpoint adjustment are available:
a, Local Setpoint Adjustment-The setpoint is
adjusted directly on the controller.
b. Remote Setpoint Adjustment-The setpoint is
controlled from 0 to 100 percent of primary sensor
span from a remote 3 to 15 psi (21 to 103 kPa)
bleed-type switch or controller feeding Port 8.
Restricted air is supplied to Port 8 by the
controller.
NOTE:
Remote adjustment can be either Remote
Setpoint Adjustment or CPA but not
both.
C. Control Point Adjustment (CPA models only)---
Thd baseline setpoint on the controller can be
adjusted percent of the primary sensor span
from a remote 3 to 15 psi (21 to 103kPa)signalinto
4
Fig. 18. Setpoint Adjustment.
LOCAL SETPOINT ADJUSTMENT
See preceding 2a.
If the scale overlay is used, insert the overlay between
the knob and transparent overlay retainer_
Note the position of the key and notch.
Using the setpoint knob, adjust the setpoint according
to the job drawings,
3.
Calibrate only if the control point deviates
significantly from the setpoint, taking into
consideration the throttling range.
REMOTE SETPOINT ADJUSTMENT
See preceding NOTE 2b,
1. Adjust the setpoint knob to 100 percent or to the
maximum desired.
2, Install Barb Fitting 14003755-001 to Port 8 and
connect to a bleed-type remote setpoint device (e.g.,
SP970) and 0- to 30-psi gage,
85-0142
12

CONTROL POINT ADJUSTMENT (CPA Models Only) COMPENSATION STARTPOINT ADJUSTMENT (RP920B and
D)
1. Pipe the CPA device to Port 9.
NOTE: A 1 psi change in the CPA pressure causes a
change of 2.5 percent of the primary sensor
span.
2. Set the CPA to the center of its range when calibrating
controllers. For example: Set the CPA to 9 psi (62
kPa)
for a 3- to 15-psi (21 to 103 kPa) signal range.
PROPORTIONAL BAND ADJUSTMENT
Adjust the Proportional Band (PB) according to the job
drawings with the proportional band adjustment knob (Fig.
14).
PB = Operating Throttling Range
Primary Sensor Span
AUTHORITY ADJUSTMENT (RP920B and D)
Adjust the authority according to the job drawings with
the authority adjustment knob (Fig. 14). Calculate the
authority setting as follows:
Negative compensation:
ASC
Positive compensation:
A C x
Where (in measured variable units):
AC =
Authority
ASC =
Compensation sensor operating range
scs =
Compensation sensor span
ASP =
Primary sensor operating range
SPs
Primary sensor span
Throttling range in measured variable (use 0
for
RP920D)
If the authority is greater than 300 percent or
must be calculated using pressure units, see
RP920A-D Modular Pneumatic Controller
Engineering Data 77-6082.
NOTE: Calibration can cause the actual
authority setting to vary from the
calculated value.
Adjust the compensation startpoint according to the job
drawings with the compensation startpoint adjustment
knob (Fig. 14). If the startpoint is not in percent, convert it
to a percentage of the compensation sensor range. See
APPENDIX A.
RESET TIME ADJUSTMENT (RP920C and D)
Adjust the reset time according to the job drawings with
the
reset time adjustment knob (Fig, 14). When the system
is in operation and stable, decrease the setting a little at a
time until the system becomes unstable. Increase the setting
slightly until the system becomes stable.
COVER
a cover is used, snap it straight on from the front. The
cover is secured by tightening the self-tapping screw in the
lower right comer.
13 85-O 142

TROUBLESHOOTING
Table 3 lists the problems and solutions in
troubleshooting in RP920 Controller,
Table 3. RP920 Problem-Solution Chart.
Problem Solution
1. When setpoint is changed in both directions, BLP Replace
setpoint module and recalibrate,
does not reach the minimum of 0.5 psi (3.5
kPa) or
maximum of 2 psi (14
kPa) below mainline pressure.
2.
BLP does not react properly or reacts too slowly.
3.
Continuous bleed-off at Port 4.
I
4.
Air leak at BLP test tap. Plug with 14002172-001 Gage Tap Repair Plug or
renlace connector block module.
When authority setting is changed in both directions,
BLP does not change.
RP920B and D only:
Replace switch block module (with startpoint
prv).
Compensation startpoint cannot be changed by Recalibrate if needed.
adjustment of compensation startpoint knob.
10. No air is supplied to primary sensor (Port 3) with Replace connector block module.
restriction switch in the unblocked position.
11.
Air leaks at Port 3 with restriction switch in blocked Tighten restrictor switch screw or replace connector
position.
block module.
12. Air leaks at restrictor switch.
13. Controller produces unacceptable noise (high
frequency humming). Identify which prv is generating the noise by touching
the related adjustment knob or screw until noise changes.
If source is
setpoint or operating point prv, replace
setpoint module. If source is in compensation startpoint
prv, renlace switch block. If needed, recalibrate,
REPAIR
The following repair procedures cover recommended
repair for the RP920 as listed in the PARTS AND ACCES-
SORIES section under PARTS LIST.
NOTE? Before doing any repair on the RP920, shut off
system air and disconnect all tubing from ports.
2.
3.
Install the new gasket and secure the replacement
module to the base with the screws.
Connect and turn on the system air. Perform the
operational check.
SETPOINT KNOB REPLACEMENT
MODULE REPLACEMENT
1. Remove the module to be replaced, including the
gasket, by loosening the screws
Simply lift off the
setpoint knob and replace it with the
new one (Fig.
85-0142
14

FILTER/O-RING REPLACEMENT IN
CONNECTOR BLOCK MODULE
Loosen the four screws securing the connector block
module to the base (Fig. 19).
2. Loosen the screw securing the restrictor switch until
the connector block module can be lifted from the
base.
3.
Remove the screw and restrictor switch (Fig. 20).
4.
Using a wire or large paper clip, push through the hole
(Fig. 20). The filter and O-ring will fall out.
5. Install the new filter and O-ring.
6. Secure the restrictor switch to the connector block
module with the knob on restrictor switch positioned
between the two stops.
7. Secure the connector block module with the four
screws.
SCREWS(4)
RES
CONNECTOR
BLP TEST TAP
19442-3
Fig. 19. Connector Block Module Parts Identity.
GAGE SEAL REPLACEMENT
Remove the gage or gage plug (Fig. 20) from the
connector block module or switch block module.
2. Insert a wire or paper clip into the hole in the center of
gage seal and gently pry out the old seal.
3. Insert the new seal, small end down. Use the point of
a ball point pen to seat the seal.
4. Replace the gage or gage plug,
RESTRICTOR
SWITCH
GAGE PLUG
/--GAGE SEAL
I
22879
Fig. 20. Filter/O-Ring, Gage Seal Replacement Diagram.
15
85-0142

PARTS AND ACCESSORIES
PARTS LIST
Table 4. RP920 Parts List (Refer to Fig. 13).
14004276002
14004277-003
14004277-004
14004278-002
14004283-002
14004283-003
14004533-001
14004533-002
43188083-002
43188059-001
14004290-002
43 187524-001
43915905-l 10
14001865-001
14002172-001
14003757-001
Includes Gage
Seal and Plug
ACCESSORIES
1.
Add-On Barb Fitting 14003755-001.
6.
Cover (Clear Plastic):
2. Gage 305965 (0 to 30 psi).
43188057-010-RP920A.
3.
Gage Adaptor 315161A with plug-in fittings. 43188123-010--RP920B,
C, and D.
4. Receiver Gage to match primary sensor (see
7.
Temperature, humidity, dewpoint, and cooler-
Pneumatic Indication, Receiver, and Target Gages
warmer setpoint scales 14004267-001.
Specification Data 77-609
1).
8.
Static pressure
setpoint scales 14004267-002.
5. Controller Calibration Kit 816A.
9.
Rail mounting bag assembly (25 sets) 14004322-001.
APPENDIX A
Table 5. Sensor VaIue to Pressure or Percent of Span Conversion Chart.
Humidity Sensors
85-0142 16