Robertshaw CR-101-A1 User manual

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INSTRUCTION MANUAL
FOR
Adjustable Bias Volume Booster Relay
CR-101-A1
Industrial Products Division
1602 Mustang Drive
Maryville, Tennessee 37801
Phone: [phone] Fax: [phone]
INSTRUCTION MANUAL NUMBER
P-2167
Rev. A
Note to installer: Before installing, read instructions carefully and record
model number. After installing, give this manual to operating personnel o
r
see that it is filed for future reference.

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NOTES:

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A. DESCRIPTION:
The Model CR101-A1 Volume Booster Relay is a
proportioning unit designed for use in pneumatic control
systems where the application requires amplifying the volume
of control air or biasing the control air pressure.
Equation: PO= P1±FS
Where POis the output pressure, P1is the input
pressure and FSis the bias.
The relay components are made of steel and aluminum, and
the diaphragms are Buna-N on nylon.
B. TYPICAL APPLICATION:
Improves the response time of a control circuit by boosting the
air volume from a simple "non-relay" controller to a control
valve, and to shift ("bias") the signal range so as to get the best
control valve action under the conditions of pressure and
pressure drop within the valve.
C. SPECIFICATIONS:
DESIGN DATA
INPUT PRESSURE RANGE (P1):
0 to 20 psig (0 to 1.4 bar) nominal
50 psig (3.5 bar) maximum
SUPPLY PRESSURE......................30 psig (2.1 bar) nominal
60 psig (4.2 bar) Maximum
(Should always be at least
10 psig (0.7 bar) greater
than output pressure.)
BIAS ADJUSTMENT (FS).........................±18 psig (1.2 bar)
OVERLOAD PROTECTION ......... 100 psig (7 bar) will not
damage unit
AMBIENT TEMPERATURE LIMITS....... -40°F to 180°F
(-40°C to 82°C)
CONNECTIONS ............... 1/4" female NPT for input, output
and supply, 1/16" NPT for exhaust
WEIGHT..........................................................1.2 lb (0.54 kg)
PERFORMANCE DATA
ULTIMATE SENSITIVITY ....................0.1% of full range
LINEARITY .................................................1% of full range
HYSTERESIS........................................ ±0.3% of full range
REPEATABILITY....................................0.5% of full range
SUPPLY PRESSURE EFFECT:
Change in output pressure for 5 psig (0.35 bar) supply
pressure change, less than 1% of full range
AMBIENT TEMPERATURE EFFECT:
Change in output for a 75°F (24°C) ambient
temperature change, 0.5% of full range
AIR CONSUMPTION ..........................3.0 SCFH maximum
FOR MAXIMUM FLOW:
Supply Output Capacity ..................... 3.0 SCFM nominal
Exhaust Output Capacity ................... 5.0 SCFM nominal
LOAD EFFECT (CONTROL AIR TO CAUSE 1 PSIG
(0.07 BAR) PRESSURE DROP: ..........................1.0 SCFM
MINIMUM OUTPUT PRESSURE (PO)..........0 to 0.5 psig
(0 to 0.03 bar)
SECTION I - GENERAL INFORMATION

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A. GENERAL:
Be sure that all pipes and fittings used are clean, free of chips,
dirt and moisture. If pipe compound or shellac is used, apply a
small amount above the second or third male thread only.
DO NOT GET PIPE COMPOUND OR SHELLAC INSIDE
RELAY.
B. MOUNTING:
When installing the relay do not remove the "Caplugs" (plastic
plugs) from the connections until ready to install fittings.
The relay may be mounted in any position. Due to its size and
weight, it may be supported by the air lines. If more secure
mounting is desired, use the mounting bracket furnished as
shown in Figure 1. Use two 1/4" bolts, toggle bolts or wood
screws as required by the installation. Bracket may be
removed or inverted by removing lock nuts.
C. CONNECTIONS:
The input, supply and output ports are 1/4" female NPT. The
exhaust port is 1/16" NPT. Make the air connections to the
proper ports as shown in Figure 1. The air supply must be
clean, dry and regulated (use filter - regulator #97478) and
must not exceed 60 psig (4.2 bar).
Air pressure in the input chamber exerts a downward force on
the input diaphragm. This force moves the center assembly
down, closing the exhaust valve. Further movement opens
the lower portion of the valve allowing the supply air
pressure to enter the output chamber. This air acts on the
control diaphragm and also passes out through the output
port. As the increasing output pressure approaches the input
pressure, the center assembly will begin to rise, permitting
the valve to close, throttling the flow of supply air. When the
output pressure equals the input pressure, both surfaces of the
valve will be closed and the relay will be in balance.
A further increase in the signal pressure will cause the lower
portion of the valve to open until the output pressure again
SECTION II - INSTALLATION
SECTION III - OPERATION
Figure 1
THIS RELAY WILL WORK PROPERLY WHEN MOUNTED IN
ANY POSITION.
Figure 2

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equals the input pressure. A decrease in the input pressure will
allow the output pressure to force the center assembly upward,
opening the exhaust valve until the output pressure is equal to
the input pressure.
A. BIAS ADJUSTMENT:
With normal supply pressure and input (signal) pressure
applied, the Bias Adjusting Screw (Figure 2) may be turned
clockwise to increase the output (control) pressure or
counterclockwise to decrease output pressure.
B. RATIO ADJUSTMENT:
The ratio of input to output pressure may be adjusted by
adjusting Valve Seat (17) as follows (see Figure 3 except
The simplified design of this relay makes routine maintenance
unnecessary. However, should the air or air lines be dirty, it
may be necessary to clean the surfaces of the Valve (18) and
the Valve Seats (A) and (B). If continued difficulty is
experienced from dirt, moisture, oil, etc., suitable filters should
be provided in the supply lines.
If the control pressure does not go below 0.5 psi with the Bias
Spring (Figure 2) in the null position, or if the exhaust appears
to be leaking (refer to Figure 3 except as noted) and follow the
instructions below:
1. Remove the Cap (24) and Spring Retainer (20) by
unscrewing from the Cover (22). Note position of Spring
Retainer (20) before removing so that it can be replaced in
approximately the same position. The Valve (18), Valve
Spring (19) and Gasket (23) are now free to fall out. Be
careful not to drop the parts.
2. Using a CLEAN, soft brush, cloth or paper, wipe off the
Valve Seats (A) and (B).
3. Inspect both Hemispherical Surfaces (C) of the Valve (18)
for dirt, chips, etc. If any scars or imperfections are
apparent, the Valve (18) should be replaced.
4. Replace the Valve (18), Valve Spring (19), Spring
Retainer (20), Gasket (23) and Cap (24). Be sure that the
Spring Retainer (20) is in the same position as it was in
before disassembly, approximately one turn below being
flush with end of Adjustable Seat (17) and that the Cap
(24) is tight. Check Cap (24) for external leakage.
5. Adjust per Section IV if needed.
DO NOT USE ANY GASKET SHELLAC, PIPE
COMPOUND, OR OTHER SEALANT.
To adjust the bias for an advanced or retarded output, turn the
adjusting screw clockwise or counterclockwise respectively,
to change the force exerted by the biasing spring.
where noted):
1. With a supply pressure of 30 psig and an input pressure
of 3 psig, turn Bias Adjusting Screw (Figure 2) until
output pressure is 3 psig. Increase input pressure to 15
psig and check output pressure, which should be 15 ±0.2
psig.
2. If necessary, remove Cap (24) and adjust Valve Seat (17)
until the correct output pressure is obtained.
3. Repeat steps 1 and 2 until the correct ratio is obtained.
This unit may be adjusted while operating with Cap (24)
removed, but the final setting must be checked after the
Cap (24) has been replaced.
SECTION IV - ADJUSTMENTS
SECTION V - MAINTENANCE

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.
If the procedure outlined in Section V (MAINTENANCE)
fails to restore proper operation, disassemble the relay as
shown in Figure 4 (except as noted) and follow the instructions
below:
1. Inspect air passages for dirt.
2. Inspect the Valve (18) surfaces for bumps, scars or other
irregularities. The Hemispherical Surfaces (C in Figure
3) must be smooth and regular.
3. Inspect the Valve Seats (A and B in Figure 3) in the Base
(15) and Exhaust Valve Plate (14). The surfaces must be
clean and smooth with no scars or surface irregularities.
4. Inspect Diaphragms (6) and (13) for holes or worn spots
which might permit air leakage.
5. Install the Valve (18), Valve Spring (19) and Spring
Retainer (20) and make sure that the Valve Spring (19) is
seating the Valve (18) properly.
6. Replace any worn or defective parts and reassemble the
relay.
DO NOT USE ANY GASKET SHELLAC, PIPE
COMPOUND, OR OTHER SEALANT.
7. With Supply and Input air pressure connected, check the
unit for external leakage.
8. Follow procedure in Section IV (ADJUSTMENTS).
CAUTION: If cleaning is required, do not subject the
Diaphragms (6) and (13) to cleaning fluids or solvents.
SECTION VI - REPAIR
26 HEX NUT
27 SEALING WASHER
28 COVER
1 ADJUSTING SPRING
ASSEMBLY
2 HEX NUT
3 WASHER
4 WASHER
5 SPACER
6 INPUT DIAPHRAGM
29 EXHAUST PLATE
7 GASKET
8 SUPPORT RING
9 VALVE MID PLATE
10 WASHER
11 ADJUSTING RING
12 ADJUSTING RING
13 BALANCING
DIAPHRAGM
14 EXHAUST VALVE
PLATE
15 BASE
30 SCREW (2)
16 O-RING
17 ADJUSTABLE SEAT
18 VALVE
21 O-RING
23 GASKET
24 CAP
31
19
20
25
22
SCREW (2)
VALVE SPRING
SPRING RETAINE
R
O-RING
VALVE COVE
R
Figure 4

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REPAIR PARTS
ITEM DESCRIPTION PART NUMBER QUANTITY
¼EXHAUST SEAT ASSEMBLY (contains items 1 thru 14) 081033F0001 1
1 ADJUSTING SPRING ASSEMBLY 081249A0001 1
2 HEX NUT, 1/4-20 027939A0001 1
3 WASHER 027947A0001 1
4 WASHER 027946A0001 1
5 SPACER 029533A0001 1
6 INPUT DIAPHRAGM 027932B0001 1
7 GASKET 027944A0001 1
8 SUPPORT RING 027943A0001 1
9 VALVE MID PLATE 027600C0001 1
10 WASHER 029360A0001 1
11 ADJUSTING RING 029185A0001 1
12 ADJUSTING RING 027677A0001 1
13 BALANCING DIAPHRAGM 027588B0001 1
14 EXHAUST VALVE PLATE 027935A0001 1
15 BASE 027668C0001 1
¼VALVE ASSEMBLY (contains items 16 thru 22) 081650A0001 1
16 O-RING 036240N0014 1
17 ADJUSTABLE SEAT 029352A0001 1
18 VALVE 026059C0001 1
19 VALVE SPRING 029359A0001 1
20 SPRING RETAINER 029354A0001 1
21 O-RING 036240N0018 1
22 VALVE COVER 029353A0001 1
¼23 GASKET 029356A0001 1
¼24 CAP 029355A0001 1
¼25 O-RING 036240N0119 1
¼26 HEX NUT, 1/4-28 036602A1800 1
¼27 SEALING WASHER 037723A0001 1
28 COVER 027930A0001 1
29 EXHAUST PLATE 028571B0008 1
30 CAP SCREW, 1/4-20 X 1-1/2 036617E2600 2
31 CAP SCREW, 1/4-20 X 1-3/4 036617E2800 2
32 MOUNTING BRACKET (not shown) 029139A0001 1
33 HEX NUT, KEPS, 1/4-20 (not shown) 036603A0019 2
Note: A Repair kit, part number 083405A0001, is available for rebuilding relay.
The Repair kit contains parts marked thus ¼.

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An invensys company
Industrial Products Division
U.S.A and Canada
Robertshaw Industrial Products Division
1602 Mustang Drive
Maryville, Tennessee 37801
Telephone: [phone] Fax: [phone]
http://www.robertshaw.thomasregister.com
http://www.robertshawindustrial.com
Exports
Invensys Appliance Controls
1701 Byrd Avenue
P.O. Box 26544
Richmond, Virginia 23261-6544
Telephone: [phone] Fax: [phone]
Q-1345 (4/03) Printed in U.S.A.