Leslie Controls Pilot Controller User Manual
Asubsidiary of International, Inc.
12501 Telecom Drive, Tampa Florida
ADJUSTABLE PROPORTIONAL BAND PILOT CONTROLLERS (PDAP and PRAP Types)
SECTION I — INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
SECTION II —OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
SECTION III — MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5
SECTION IV — SETTING OF ADJUSTING PIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6
INSTALLATION, OPERATING,
AND MAINTENANCE INSTRUCTIONS
33637
PARTS LIST
LESLIE PILOT CONTROLLERS
TABLE OF CONTENTS
20/1.5.2
Rev.3
STEM LENGTH AND SENSITIVITY ADJUSTMENT (PRA-
CONSTANT PRESSURE PILOT CONTROLLERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
CONSTANT, DIFFERENTIAL PRESSURE AND RATIO PILOT CONTROLLERS
Force Balance, Fixed Band Types
SECTION I — INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
SECTION II — OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
SECTION III — MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
PARTS LIST . . . . . . . .
ILLUSTRATION INDEX
DRAWING, DIMENSIONS, TYPICAL INSTALLATIONS AND MISCELLANEOUS DATA
Figure 1 - Pilot Controller Piping Details - Pressure Reduction Station . . . . . . . . . . . . . . . . . .2
Figure 2 - Pilot Controller with 1:1 Volume Booster Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Figure 3 - Pilot Controller wit 1:1 Volume Booster and Reset Relay . . . . . . . . . . . . . . . . . . . . .3
Figure 4 - Pilot Controller with
Figure 5 - Pilot Controller with Inverse Derivative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Figure 6 - Type PRAP Pilot Controller (5-80 psig range) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Figure 7 - Type PDAP Pilot Body Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Figure 8 - Position of sliders for nut/blade spring adjustment . . . . . . . . . . . . . . . . . . . . . . . . .5
Figure 9 - Min./Max. Proportional Band Table .
Figure 10 - Adjustable Proportional Band Pilot Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Figure 11 - PRA-1, PRW-1, PRQ, Pilot Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Figure 12 - Pilot Controller piping details — Typical Installation . . . . . . . . . . . . . . . . . . . . . . . .8
Figure 13 - Drawing showing Direct Acting Type Pilot Controller (PDA-1, etc.) . . . . . . . . . . . .9
Figure 14 - Partial Drawing showing lever and lever pin
Figure 15 - Diaphragm assembly for Pressure Ranges 13 PSIA - 20 PSIG to 50-125 . . . . . .11
Figure 16 - Back Pressure or Pressure Relief Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Drawing - Pilot Controllers Types PDA-1, PDQ-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Drawing - Pilot Controller Types PRA-1, PRA-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Drawing - Pilot Controller Type PDAP-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drawing - Pilot Controller Types PRAP-1, Range 5-70 & 50-800 . . . . . . . . . . . . . . . . . . . . .20
Drawing - Differential Pilot Control Type UDDV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Drawing - Pilot Controller Type DDD, 15-75 Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Positioner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
1 and PRQ-1 Types)
14-25
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
tc. . . . . . . . . . . . . . . . . . . . . . . . . . .9
, e
. . . . . .
18
5
6" Vertical Section (Min.)
Air Lines-Use 1.4" I.D. pipe or tubing.
Use noncorrosive pipe and fittings.
Connect air supply to Pilot Controller
under gauge marked Operating Supply.
Connect outlet from P
under gauge marked Control Valves to
Diaphragm Control Valve.
LESLIE Class AF-2 Pressure Reducing
Valve. Set reducing valve to supply 2022 psig air to pilot.
ilot Controller
Figure 1. Pilot Controller Piping Details — Pressure Reduction Station
Union
Impulse LIne-Use 1/2" schedule 40 pipe or tubing
with equivalent I.D.
Avoid loops or pockets in impulse line to insure
true pressure signal to pilot diaphragm.
Slope as shown for condensible gas service 1" per
12"
foot minimum.
Slope toward pilot for steam and liquids.
Gage
Stop Valve
1"
SECTION I - INSTALLATION
Install pilot controller vertically, in an accessible location.
Allow removal space for ease of maintenance.
Pilot controller may be located above or below line controlled.
IMPULSE LINE CONNECTION AND LENGTH
Connect impulse line from top of diaphragm cover to controlled pressure line. Make connection at least 3 feet from the
valve body opening or the end of any expander. Best results
are obtained when the impulse line does not exceed 30 fe
Av
oid connections near turbulent areas such as those created by orifices, elbows, sharp bends, or other flow direction
changing components.
PITCH OR SLOPE OF IMPULSE LINE
Steam and liquid impulse lines should slope toward the sensing head. This ensures that the lines stay full of liquid or
condensate. Pre-fill the sensing line before startup.
For noncondensing gases such as air, slope the lines away
from the pilot, so that any liquid contaminants drain back to
the pr
ocess. M
inimum slope is 1" per foot.
Accessary Equipment
Volume booster relays, positioners, reset relays, derivative
units, etc. may be used with Leslie adjustable proportional
band pilot controllers where system characteristics require
their use.
et.
HYDROSTATIC HEAD PRESSURE
When the pilot controller is installed under the line controlled,
the total pressure resulting from hydrostatic head and controlled pressure must not exceed the maximum range of the
pilot co
ntroller
SECTION II - OPERATION
The pilot is factory set and requires no adjustments other than
those necessary to obtain the controlled pressure desired and
the width of proportional band required by the system.
1. Close inlet and outlet stop valves around the control
valve.
2. Open air supply line and impulse line stop valves. Set
proportional band adjustment at “Maximum Band.”
For Pressure Reducing Service Only (Refer to
Figures 6 & 7)
3. Turn adjusting nut (22) of pilot c
wise until control valve is wide open.
4. Open outlet stop valve partially. Fully open inlet stop
valve slowly.
5. Make final adjustment for desired controlled pressure
value. To increase controlled pressure screw adjusting
nut (22) counter-clockwise. To decrease pressure screw
adjusting nut clockwise.
6. Open outlet stop valve fully.
ontro
ller counter-clock-
Page 2
Pressure Reduction
Pressure Reduction
PDAP
N.O. Valve
Figure 2. Pilot Controller with 1:1 Volume Booster Relay
Pressure Reduction
PDAP
N.O. Valve
PRAP
N.C. Valve
Figure 4. Pilot Controller with Positioner. Split Ranging
may also be done.
Back Pressure
PRAP
N.O. Valve
Figure 3. Pilot Controller with 1:1 Volume Booster and
Reset Relay
For Back Pressure Service Only
3. Turn adjusting nut (22) of pilot controller counter-clockwise until control valve is fully closed.
4. Open inlet stop valve fully. Partially open outlet stop
valve. Turn adjusting nut (22) of pilot controller clockwise until control valve just begins to open. Open outlet
stop valve fully.
5. Make final adjustments for desired controlled pressure
value. To increase controlled pressure screw adjusting
nut (22) counter-clockwi
se. To d
sure screw adjusting nut clockwise.
ecrease controlled pres-
Figure 5. Pilot Controller with Inverse Derivative
ADJUSTMENT FOR REQUIRED
PROPORTIONAL BAND
Pilot controller is now ready for operation. Adjust for required
width of proportional band as follows:
Turn adjusting know (76) counter-clockwise, moving pointer
toward minimum band setting until the output air pressure
begins to cycle. Widen the proportional band until the cycling
stops.
Page 3
SECTION III - MAINTENANCE
DISMANTLING
(Refer to Figures 6 and 7)
1. Bypass the control valve if system operation is necessary during maintenance work. Shut off air supply to
pilot controller.
2. Take out body screws (36). Slide pilot body assembly
off base in a downward direction away from adjusting
pin (64).
3. Remove bottom plug (47). Remove diaphragm plate (30)
from pilot body by removing capscrews.
NOTE: Do not disturb position of proportional band
parts on diaph
them.
Take out diaphragm nozzle disc (29) remove flange ring
(37) and gasket (40). In PRAP types remove nozzle valve
(79) and spring (80).
Cleaning and Reassembling Pilot Body Assembly
1. Wipe all parts clean. Check ports in pilot body, nozzle
and orifice to be sure they are clear. DO NOT use sharp
abrasives. Open air supply and blow out supply line.
ragm p
late, unless work is required on
Figure 6. Type PRAP Pilot Controller (5-80 psig range)
*NOTE: Spring (81) and spring seat (82) are not used in the 50800 psig range PRAP Pilot Controller.
Page 4
Figure 7. Type PDAP Pilot Body Assembly
2. Replace bottom plug (47) in pilot body. Place gasket
(40) in pilot body. In PRAP types rein
(79) and spring (80). Position flange ring (37) with nozzle
upward on gasket (40). Insert flange ring screws and
tighten.
3. Insert diaphragm nozzle disc (29) in pilot body with flat
disc end toward nozzle. Replace diaphragm plate (30)
on pilot body, with knob (76) on the right hand side. If
blade spring (66) was removed from the assembly, be
sure to reassemble it with the preformed end bends
pointing upward.
Cleaning or Replacing Parts in Superstructure
NOT
E: I
f maintenance work is necessary on superstructure
alone, remove pilot body assembly from base as described in
Step 2., Section III then proceed as shown below:
sert n
ozzle valve
Dismantling Superstructure
1. Loosen setscrew (63) and disassemble adjusting pin
(64) from stem (13).
2. Remove diaphragm cover (3), diaphragm spring (81)
and diaphragm spring seat (82), diaphragm (6),
diaphragm disc (7), diaphragm spacer (15) and
diaphragm guide (16). Lift out top spring seat (17) with
stem (13), stem nut (19) and yielding spring (18).
Remove adjusting spring (12), bottom spring seat (20),
thrust bearing (21), adjusting nut (22) and locknut (23
3. Clean all parts. Replace any worn or damaged part. To
disassemble stem (13) from top spring seat (17) hold
top spring seat rigidly on hex, press down on stem and
remove stem nut from top spring seat.
REASSEMBLING SUPERSTRUCTURE
1. Reassemble locknut (23) (countersunk side downward),
adjusting nut (22), thrust bearing (21), bottom spring
seat (20) and adjusting spring (12) to adjusting sleeve
(14). Replace top spring seat (17) with assembled stem
in yoke (10). Place di
gm guide (16) in recess of
aphra
yoke (10).
2. Place diaphragm spacer (15) on yoke (10) with raised
face downward. Position diaphragm disc (7) on top
spring seat (17). Place diaphragm (6), diaphragm spring
seat (82), diaphragm spring (81) and diaphragm cover
(3) on diaphragm. Replace bolts (8) and nuts (2).
Tighten firmly. Reassemble adjusting pin (64) to stem
(13).
REASSEMBLING PILOT BODY ASSEMBLY TO BASE
proportional band nut down against blade spring until air output pressure decreases from 21 to 18 psig. With pin in stem
hole to keep stem from turning, loosen set screw and turn
adjusting pin upward away from pilot body approximately
1Z\v turns. Lock set screw.
For PRAP Adjustable Proportional Band Type
Adjust slider ZC\zn” apart as shown in sketch below. Move
proportional band nut upward on adjusting pi
hread suffi-
n t
ciently to keep nut from touching blade spring during stem
).
length adjustment. Loosen adjusting pin set screw and turn
adjusting pin either up or down until pilot air output is 21 psig.
Then turn adjusting pin downward toward pilot body until
pilot air output decreases from 21 to 0 psig. Lock set screw.
Turn proportional band nut down against blade spring until air
output pressure increases from 0 to 3 psig. With pin in stem
hole to keep stem from turning, loosen se
crew and turn
t s
adjusting pin upward away from pilot body approximately
1Z\v turns. Lock set screw.
Stem (13)
Nut (65)
Slider (70)
Figure 8. Position of sliders for nut/blade spring
adjustment
13/16"
Blade Spring (66)
Slider 975)
Knob
(76)
1. Slide pilot body assembly upward on base so that
adjusting pin (64
) p
asses smoothly through proportional
band blade spring. Replace pilot body screws (36) and
tighten firmly. Reconnect impulse line to diaphragm
cover. Open air supply line. Adjust pilot as described in
Section IV.
SECTION IV - SETTING OF ADJUSTING PIN
Supply 20-22 psig operating pressure to controller. Turn
adjusting nut to compress adjusting spring to set upper
diaphragm against its top limit stop. If possible, remove fluid
pressure from top of diaphragm, if not, comp
sufficiently to overcome fluid pressure and move diaphragm
to stop.
For PDAP Adjustable Proportional Band Type
Adjust sliders ZC\zn” apart as shown in sketch below. Move
proportional band nut upward on adjusting pin thread sufficiently to keep nut from touching blade spring during stem
length adjustment. Loosen adjusting pin set screw and turn
adjusting pin either up or down until pilot air output is 0 psig
then turn adjusting pin downward toward pilot body u
air output increases from 0 to 21 psig. Lock set screw. Turn
s spring
res
ntil p
ilot
NOTE: When the above adjustments have been properly
made, the proportional bands noted in Table - Figure 9 will be
obtained when the sliders are set the approximate distances
apart as shown.
SLIDER
PILOT TEST DISTANCE
RANGE PRESSURE BAND (PSIG)
(PSIG) (PSIG)
5-70 50 2
50-800 80 2
Figure 9. Min./Max. Proportional Band Table
MIN. MAX.
BAND BAND MIN. MAX.
3
⁄4"1
3
⁄4"1
1
⁄4" 2.0 - 4.5 7.0 - 11.0
1
⁄4" 5.5 - 8.5 15.0 - 21.
Page 5
Figure 10. Adjustable Proportional Band Pilot
Controllers
Page 6
STEM LENGTH AND SENSITIVITY ADJUSTMENT
TYPES PRA-1 AND PRQ-1
CONSTANT PRESSURE PILOT CONTROLLERS
FORCE BALANCE, FIXED BAND TYPES
ADJUSTMENT PROCEDURE
Supply 20-22 psig operating pressure to the pilot controller.
Turn adjusting nut to compress adjusting spring to set upper
diaphragm against its top limit stop. If possible remove fluid
pressure from top of diaphragm, if not compress springs sufficiently to overcome fluid pressure and move diaphragm to
stop.
AD
JUSTING R
Remove nozzle disc pin, pilot cover and diaphragm nozzle
disc.
For Normal Response Sensitivity adjust pilot controller for
very minor or no leak off. To do this relieve pressure of blade
spring on nozzle stop by pressing lightly downward on it with
finger. Then screw nozzle stop downward until it is felt to barely seat on nozzle nut.
For Supersensitive Response adjust pilot controller for continuous leak off. To do this slowly screw nozzle st
downward until operating pressure flow is just detectable
through nozzle bleed port. To check amount of leak off place
finger lightly over nozzle bleed port to seal air (do not press
down on nozzle). Air pressure in output line to diaphragm control valve should not build up any faster than 3-5 psig in 20-30
seconds. Lock nozzle stop with blade spring.
ESPONSE SENSITIVITY
op f
urther
NOTE: THIS ADJUSTMENT IS FACTORY SET and should
not be disturbed unless it is obvious that the original setting
has been changed or major parts replacements were made
which may cause need for readjustment.
These adjustments can be made when the pilot controller is
set for either continuous or non-continuous leak off.
PRA-1 AND PRQ P
1. Loosen locknut on lever setscrew. With 20 psig air pressure on out put gauge turn setscrew upward into lever
until output air pressure just begins to fall away from 20
psig.
2. Then turn lever screw downward (out of lever) 3/4 turn
for all low pressure pilots (up to and including the 50-125
psig range) 1-1/4 turns for high pressure ranges (100-
200) psig and over). Tighten locknut.
NOTE: With pilot air output at 20/22 psig, lever should be
approximately in th
nozzle disc pin locknut and screw lower section of pin into or
out of upper section of pin until lever is parallel. Tighten locknut.
e p
arallel position. If not parallel loosen
ILOT C
ONTROLLERS
To Test Pilot Controller Body and Diaphragm Control Valve
for response press downward on center of nozzle until 20-
sig air pressure registers on output gauge. Control valve
p
should move through full travel. Release nozzle. Air output
pressure should drop to 0 psig and control valve should return
to its original position.
After completing sensitivity adjustment replace diaphragm
nozzle disc, nozzle disc pin and pilot cover.
LEVER SCREW ADJUSTMENT
Desired pilot controller performance will be obtained only if the
upper (sensing) diaphragm is operating at or near its mean
position
base and cover. Its position is determined by adjusting length
of lever adjusting screw.
.e. half way between its top and bottom limit stops in
, i
22
Figure 11. PRA-1, PRW-1, PRQ, Pilot Controllers
Page 7
CONSTANT, DIFFERENTIAL PRESSURE AND RATIO
PILOT CONTROLLERS
Force Balance, Fixed Band Types
Types Covered:
PDA-1 PDW-1 PDQ-1 UDDV* DDD**
PRA-1 PRW-1 PRQ-1 UDRV* UDDD***
STOP — LOOK — READ OBSOLETE
ADHERENCE TO THESE INSTRUCTIONS
GUARANTEE OPTIMUM RESULTS
INSIST UPON THEIR BEING FOLLOWED.
SECTION I — INSTALLATION
Install Pilot Controller vertically in an accessible location.
Allow removal¬ space for ease of maintenance. Pilot
Controller may be located above or below line controlled.
NOTE: Whenever hydrostatic head exists on diaphragm effect
must be considered with
Piping Details
Figure 1 shows control pilot piping details. Control valve piping shown in figures is schematic only. Consult Control Valve
Instructions for piping details.
lation to obtainable pressures.
re
Control Pipe Connection and Length
Connect Control Pipe from top of diaphragm cover to controlled pressure line. Make connection in controlled pressure
line at least 3 feet from the valve body opening or the end of
the expander, if one is in use. Best results are obt
ained w
hen
length of control pipe does not exceed 30 feet. Avoid connections near turbulent areas such as those created by orifices, elbows, sharp bends, or other flow direction changing
components.
Pitch or Slope of Control Pipe
Pilot Above Line Controlled — Slope control pipe downward,
away from the Pilot Controller. Provide at least 6" of vertical
pipe at connection to pilot cover.
Pilot Below Line Controlled — Slope control pipe downward
toward Pilot Controller.
Hy
dro
static Head Pressure
Where the Pilot Controller is to be installed under the line controlled (and liquids or condensible gases are to be controlled)
total pressure resulting from hydrostatic head and controlled
pressure must not exceed the maximum range of the control
pilot.
AIR LINES — Use 5/16" (1/4"
I.D.) pipe or tubing. Use noncorrosive pipe and fittings.
Connect outlet of air reducing valve to
inlet of Pilot Controller (immediately
u
age marked “Operating
nder g
Supply”). Connect outlet of Pilot
Controller (immediately under gage
marked “Control Valve”) to diaphragm
connection of Control Valve.
Operating m
Reducing Valve to supply 20-22 psig
to pilot.
*NOTE: AIR CONNECTIONS — Pilot Controller is equipped
with stainless steel air supply and output fittings. DO NOT
remove. Connect air lines directly to these fittings.
edium clean air** Set
Figure 12. — Pilot Controller piping details — Typical installation
6" Vertical Section (Min.)
Union
Strainer
AVOID LOOPS OR POCKETS IN
CONTROL PIPES to insure true
pressure signal to pilot diaphragm.
Control pipe — use 1/2" 40 schedule pipe or tubing with equivalent
internal diameter
(For ranges up to and including
50-125 psig: for ranges 100-200
psig and over use 3/8" pipe).
Stop Valve
Gage
*See NOTE
**NOTE: Operating medium for Classes PRA-1, PDA-1,
UDRV, UDDV etc. (aluminum construction) must be
clean air. (Win Class designation) are suitable for oil or
water as operating medium.
cing u
*Use with Instruction 20/2.5.3 for repla
**Use instruction 20/3.5.1 for replacing upper diaphragms — DDD, UDDD Types.
pper diaphragms — UDDV, UDRV Types.
Page 8
SECTION II — OPERATION
PROCEDURE: Follow Steps 1 and 2 then proceed with
Steps 3 through 5 whichever applies to the particular service.
1. Close inlet and outlet stop valves around the control
valve.
2. Open air supply line stop valve. Adjust 1/4" reducing
valve to supply 20-22 psig pressure to control pilot.
For Pressure Reduction Installation
3. Turn adjusting nut of Pilot Controller Until diaphragm
control valve is wide open.
4. Open outlet stop valve partially and
contro
l pipe stop
valve fully.
5. Open inlet stop valve slowly, until Pilot Controller takes
hold and starts to close the diaphragm control valve.
Screw adjusting nut upward to increase, downward to
decrease the controlled pressure. After desired controlled pressure is obtained, open inlet stop and outlet
valves fully.
For Overflow Relief Installation
3. Turn adjusting nut of Pilot Controller until diaphragm
control valve is closed.
4. Open inlet, outlet, and contro
l p
ipe stop valves fully.
5. Turn adjusting nut of Pilot Controller so that diaphragm
control valve starts to open when desired inlet pressure
is exceeded.
Differential Pressure Pilot Controllers
3. Turn adjusting nut of control pilot to adjust compression
on adjusting spring until control valve is wide open.
4. Open outlet stop valve partially and control pipe stop
valves fully.
Figure 13. — Drawing showing Direct Acting Type Pilot
Controller (PDA-1, etc.).
5. Open inlet stop valve slowly, until controller takes hold
and begins to close the control v
alve. R
eadjust the
adjusting nut of the control pilot to obtain desired differential. To increase differential, when highest pressure is
on top of diaphragm, screw adjusting nut upward; to
decrease differential, screw adjusting nut downward.
When highest pressure is on underside of diaphragm
screw adjusting nut upward to decrease differential;
downward to increase. After desired differential setting
is obtained, open inlet and outlet stop valves fully.
NOTE: Whe
ystems are in full operation, use caution in cut-
n s
ting a controller in so that system differential will not be disturbed.
Page 9
DO NOT DISTURB SETTING
OF THIS PIN
Figure 14. — Partial Drawing showing lever and lever pin,
etc., in lever action Types (PRA-1, etc.,).
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