Honeywell RP920A, RP920D Service Data
RP92OD
RP920A-D
Modular Pneumatic
Controller
Service Data
TABLE OF CONTENTS
GENERAL
Description
Application
Specifications
Operation ......................................................................................................................................
RP920A
RP920B
MAINTENANCE..
Equipment Required
Inspection and Cleaning
Operational Check
All Systems
System in Operation
System not Operating-Sensors Disconnected
Calibration Check..
Calibration ....................................................................................................................................
Adjustments . . . . . . . . . . .
.......................................................................................................................................
....................................................................................................................................
...................................................................................................................................
................................................................................................................................
or C Controller..
or D Controller
........................................................................................................................
..........................................................................................................................
...............................................................................................................................
....................................................................................................................
Equipment
Pr0xdLu.e
Operating Point
Operating
S etpoint
Compensation Startpoint
RP920A
RP920B
RP920C
General
..............................................................................................................................
................................................................................................................................
(RP920A
Point
as
....................................................................................................................................
. . . . .
. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
and D
. . . . . . . . . . . . . . . . . . . . . . . . .
...............................................................................................................
...................................................................................................................
..................................................................................
and B)
Maximum
(RP920B
...................................................................................................
.......................................................................
Limit
and D)
(RP920C
.......................................................................................
D).
and
3
3
3
4
4
4
4
4
5
5
5
5
5
5
5
6
6
6
6
7
-7
9
9
9
Copyright 1993 Honeywell Inc. � All Rights Reserved
85-0142
MLF C. 6.
TABLE OF CONTENTS (Continued)
Direct to Reverse Acting
Negative to Positive Compensation
Integral Action Cut-Off and Gage Function
Setpoint
Adjustment
Local Setpoint Adjustment
Remote
Setpoint
Adjustment
......““““““.““.““.“““.‘..“‘.““.
(RP920B
and D)
(RP92OC
..“““.“‘.“.“‘.““.““““‘.““““““.“““‘.““““.“‘.““‘.‘.‘..“..“..--.‘.
..““““““““““‘.““‘.‘.“.‘..““.“““‘....“*“‘.““.““..“““..“‘...‘*.‘..‘...“.
Control Point Adjustment (CPA Models Only)
Proportional Band Adjustment
Authority Adjustment
Compensation Startpoint Adjustment
Reset Time Adjustment
Cover
....*...“‘.‘....““..‘..“.“‘.‘...“..“‘.““.“..“.‘.“‘.““‘..“..‘..““.“.‘...*....“....‘.““..‘.“‘.‘..**.*.......‘...
TROUBLESHOOTING
(RP920B
and D)
(RP920B
(RP920C
and D)
..““.““““..““‘.“““““‘....“‘*‘.‘.‘.‘.‘.““““““..““....“.‘...f..
...*“‘...‘..‘.‘..“.‘.‘..“‘.“..“.“...‘
REPAIR... . . . . . . . . . . .
Module Replacement
Setpoint
Knob Replacement
..““.“““““...“........‘..“‘.‘
..‘..““““““.“‘..“‘.*“.“‘.‘.‘.“.“.“.“.““‘.‘
Filter/O-Ring Replacement in Connector Block Module
Gage Seal Replacement
PARTS AND ACCESSORIES
Parts List
Accessories
APPENDIX A
......““‘*....“‘*“““.“““““‘
..*“.“...‘.‘.“““‘..“““‘
..““..“.““.“.“.‘.“
..‘..‘.“.“.‘.“‘.“““...“‘.‘.“‘.“““‘...‘.‘.‘*“.‘.‘....‘.“.“‘..‘....‘.‘..“*‘.X‘.‘.....“.‘.‘..
..“.“.“‘.‘.“‘.“.‘.f*“
..“.“.“‘.‘.““.“.‘.‘......‘........*...
and D)
..“‘.“.“....“....t.“‘...
..““““..““.‘.“““‘.““.‘.‘.““*““.“““.‘..‘...*..tl.
..“““..““.““‘...‘n‘..“......‘f...s
..,‘.“““‘..“.‘...*..‘..
...‘.“‘..‘.*‘.“.““‘.“‘..‘.1..‘.‘.*..--...
and D)
..‘.“““..“.‘..“‘*.“.*..
....‘..*‘.““‘.‘.“.‘.“....‘.*...“‘
.
11
11
11
12
12
12
13
13
13
13
13
13
14
14
14
14
.
15
15
16
16
16
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.
sensor modulates the outdoor and return air dampers
MIXED AIR CONTROL SYSTEM
Fig. 1 Typical Single-Input Controller Applications.
l),
the primary
LIMIT
CONTROLLER
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.
l),
In the hot water converter control application (Fig.
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
4 8 9
2 3 1
r-l
STEAM
SUPPLY
HOT WATER CONVERTER
CONTROL SYSTEM
r
, MODELS ONLY
CPA
OR C
DA
PRIMARY
SENSOR
IN HWS
TO CONVERTER
LINE
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
COMPENSATION
WHERE:
FULL
COMPENSATION SENSOR
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
COMPENSATION
START
21365-l
Fig. 3. Compensation Reset Schedule.
3
VALUE.
85-O 142
SPECIFICATIONS
OPERATION
Models:
RP920A:
RP920B:
RP920C:
RP920D:
Main Air Supply:
18
Minimum Air Pressure:
15
Maximum Safe Air Pressure:
30
Input Signal:
3
to 15 psi (21 to 103
Output Signal:
3
to 13 psi (21 to 90
Air Consumption:
RP920B
Sensor:
Air Capacity:
0.07
Single-Input Controller
Dual-Input Controller
Single-Input P + I Controller
Dual-Input P + I Controller
psi (124
psi (103
psi (207
pressure difference
kPa)
kPa)
kPa)
and
and D:
scfm
(33.0 ml/s) at
minimum
C:
kPa)
kPa)
scfm
0.021
scfm
0.046
0.019
scfm
sensor selected
18 psi
(9.9 ml/s)
(21.7 ml/s)
(9.0 ml/s) depending on
(124kPa) with 1
psi (7 kPa)
RP920A
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.
primary sensor in the hot water supply
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
change the control point temperature percent x the
sensor span.
RP920B
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 temperature according to a predetermined compensation reset
schedule (Fig. 3).
application because of the integral action.
OR C CONTROLLER
In the mixed air control system with high
In the hot water converter control system
from
from
open to closed. If the CPA is used, it can
OR D CONTROLLER
In the dual-input control system
The RP920D
(Fig.
2),
the
provides finer control in this
limit
(Fig. 1),
(Fig.
l), the
the converter
setpoint
of
Proportional Band:
2.5 to
50%,
field adjustable
Authority
5
Compensation Start Point
0
Integral Reset Time
0.5 to 20
Ambient Temperature:
40
(RP920B
to 300% of primary sensor span
to 100% of compensation sensor span
minutes, field adjustable
to 130F (5 to 55C)
and D Only):
(RP920B
(RP920C
and D Only):
and D Only):
MAINTENANCE
EQUIPMENT REQUIRED
1.
Gage 305965 (0-
2.
Gage Adaptor 729 with plug-in fittings.
3.
Receiver Gage to match primary
matic Indication, Receiver, and Target Gages Specification Data 77-6091).
4.
Barb Fitting 14003755-001 (integral models).
5.
Controller Calibration Kit
6.
Pneumatic Calibration Kit
to
30-psi).
MQP8
sensor
16A,
(see Pneu-
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
NOTE: Once removed, self-tapping screws can be a
or dirt from th e RP920.
and
D).
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/
of the throttling range as set by the authority and
compensation startpoint. If a discrepancy exists,
recalibrate the controller.
Move th e setpoin t slightly up and down. The BLP
4.
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 t and CPA to the
original settings,
NOTE: The
RP920C
or D should maintai ncontrol
closer to th e setpoin t or reset schedule than
the RP920 A or B because of the integral
action.
OPERATIONAL CHECK
ALL SYSTEMS
Be certain all adjustment settings and conditions are
correct. See job drawing s
of the adjustments available on each model.
Table 1 . RP92 0 Adjustments.
Adjustment
Proportional Band
Internal restrictor
switch
Direct/reverse acting
(proportional
module position)
Authority
Positive/negative
compensation (switch
block module position
Reset time
Gage/integral cut-off
(switch block gasket
SYSTEM IN OPERATION
Be certain th e
Observe BLP. If it is not between 3 and 13 psi (21 to
90 kPa) , slowly adjust th e setpoin t knob and/or CPA
Allow the system to stabilize before continuing.
Measure the temperature, humidity, or static pressure
at the main sensor. This should agree with th e
of the
throttling range .
measurement should agree with the reset schedule
for
prope r
settings. Table 1 is a list
Model
X X X X
X X X X
X
I Xl X I X
X
I
HVAC
X X X
I I
X
X X
equipment is functional.
For
theRP920B andD
0 kPa ) range. until the BLP is in the 3 to 13 psi (21 to 9
setpoint
X
X
the
SYSTEM NOT OPERATING-SENSORS
DISCONNECTED
EQUIPMENT
0- to pressure gage.
Restricted air supply, adjustable from 3 to 15 psi (21
kPa) ,
to 10 3
with receiver gage to match sensors or
Sensor Controller Calibration Ki t MQP816A.
Pneumatic Calibration Kit MQP80 0 (optional).
PROCEDURE
1.
Connect the 0- t o30-psi gage to Port 2 (branch).
Connect the main air supply to Port 1 (18 psi
2.
minimum).
3.
Pipe a 3 to 15 psi (21 to 10
kPa ) adjustable air 3
supply with a receiver gage which matches the
primary sensor to Port 3.
4.
Pipe a second 3 to 15 psi (21 to 10
3kPa ) adjustable
air supply with a receiver gage which matches the
compensation sensor to Port 5 of an
5.
If checking a CPA model, pipe 9 psi to (62 to
Port 9. The
or can be used to
supply 9 psi (62
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
(55
to the integral module. This prevents
integral action. Without this procedure, it is
necessary to allow additional time for the controller
to finish responding to any change in input pressure
or settings.
and
a .
Adjust the input air pressure to Por 3t to
correspond with the mid-point of the throttling
range of the primary sensor (see APPENDIX
A).
or D.
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
8.
RP920B
a.
and D:
Plot the reset schedule to determine the
10.
corresponding compensation and primary
sensor values.
Convert the reset schedule value to pressure
b.
(See APPENDIX A) and adjust the air supplies
to those pressures. For an
should be 8 psi (55
kPa).
RP920D,
For an
the BLP
RP920B,
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.
Move the
a,
kPa).
setpoint
knob until the BLP is 8 psi (55
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.
Slowly decrease the
b,
setpoint
one division. The
BLP should change proportionally in the
opposite direction of Step
For CPA models, repeat Steps 9a and 9b
c.
substituting the
If the controller works properly, go to Step 11. If
d.
CPA knob
9a,
for the
setpoint
knob.
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
Return to Step 9.
Connect the tubing and make settings according to
11.
the job drawings.
the
BLP
Throttling range =
Proportional Band = 5 percent.
Setpoint = 1OOF
180
160
k-z@ 140
100
-10
220
200
180
140
I
100
-10 0 20 30 40 50 60 70
0
TO 13-PSI (21 TO 90 THROTTLING RANGE
(or 30 percent).
10 60 70
OUTDOOR AIR TEMPERATURE
(COMPENSATION SENSOR)
OUTDOOR AIR TEMPERATURE
(COMPENSATION SENSOR)
DIRECT ACTING
(21 TO 90 RANGE
DIRECT ACTING
13 PSI (90
THROTTLING RANGE
3 PSI (21
13 PSI (90
THROTTLING RANGE
3 PSI (21
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.
NOTE: On the
integral module with the seal screw. Be sure the
RP920C
and D, replace fitting in 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.
From APPENDIX A the input pressures are:
Port 3 (primary) 9 psi (62
Port 5 (compensation) =
The BLP should be 8 psi (55
for
kPa)
NOTE:
RP920B
Previous discussion and illustration assumes 3 to
13 psi (21 to 90
7.3
psi (50.3
kPa) for RP920D,
kPa)
operating range. However,
the controller may be calibrated to match the
spring range of the actuator (e.g., 4 to
expected BLP at the would then be the
center of the actuator spring range (e.g., 7.5 psi).
6
kPa).
or 9 psi (62
11
psi). The
CALIBRATION CHECK
TheRP920 is factory calibrated.
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.
Adjust the proportional band to 50 percent and set for
3.
direct acting.
4.
If the BLP is 8 psi (55 kPa), go to Step 5.
the setpoint knob (Fig. 6) and turn the operating point
screw with a 5/64-inch Allen wrench until this value
is matched,
Reinstall the self-tapping screw in Port 8.
5.
If
the
controller
If
not, remove
does not
OPERATING POINT AS MAXIMUM LIMIT
(RP920C
1.
and D)
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)
MLP_
2.
Adjust the setpoint to 50 percent. On the
adjust the compensation module to negative compensation and set the compensation startpoint to 30 percent.
3.
Adjust the proportional module to direct acting and
set the proportional band to 50 percent.
4.
Adjust the reset time to 15 minutes.
If the BLP is 17.5 psi (120 kPa), go to Step 6. If not,
5.
remove the setpoint knob and turn the operating point
screw with a 5/64-inch Allen wrench until this value
is matched.
Reinstall the self-tapping screws in Port 8 and in the
6.
top of the integral module.
minimum
RP920D
Fig. 5. Connections for Operating Point Check-RP920A
and B.
OPERATING POINT SCREW
MODULE
KNOB
Fig. 6. Operating Point Screw Location.
Fig. 7. Connections for Operating Point Check
and
SETPOINT
1.
Pipe the connections (Fig. 8). Install Barb Fitting
14003755-001 in Port 8.
2.
Apply
MLP.
Adjust the setpoint knob or screw until the gage
3.
reading is 9 psi (62 kPa).
4,
The setpoint knob setting should be 50
not, remove the setpoint knob and replace it oriented
to 50 percent.
5.
Reinstall the self tapping screw in Port 8.
(RP920C
percent. If
85-0142
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