4660 Pressure Pilot
Instruction Manual
Form 5200
September 2004
11
3. Push the small button in the center of the knob
with a ball point pen or pencil and rotate the scale
with the thumbwheel on the right hand edge of the
module (see figure 5) until the number 50 aligns with
the mark on the left-hand edge of the module
window.
4. Rotate the locking arm counterclockwise to lock
the module.
5. Repeat steps 1, 2, and 3 for the other module, if
specified.
Prestartup Checks
Before using the pilot in an actual startup, verify that
both the high and low set point pressures are set at
the desired pressure settings.
WARNING
To avoid personal injury or property
damage caused by a sudden release of
pressure, do not exceed the Bourdon
Tube rating (see tables 2 and 3).
1. After the desired low set point pressure has been
adjusted, increase the external pressure source
pressure until the output pressure of the pilot is at
full output. Do not exceed the set range (see tables
2 and 3) for the appropriate Bourdon tube range.
2. Increase the external pressure source pressure
until the output pressure of the pilot has changed
from full output to zero. Listen carefully. You will
hear a quick change in sound when the output
changes.
3. Compare the pressure of the external pressure
source with the desired high set point setting.
4. If necessary, adjust the high set point pressure by
turning the HIGH SET knob clockwise to increase
and counterclockwise to decrease the high set point
setting. Once the desired high set point is achieved,
rotate the locking arm to the locked position.
5. Decrease the external pressure source until the
output pressure of the pilot is again at full output.
6. Continue to decrease the external pressure
source pressure until the output pressure of the pilot
has changed from full output to zero. Listen
carefully. You will hear a quick change in sound
when the output changes.
PERCENT OF BOURDON
TUBE RATING
CONSTRUCTION
Set Point
D
P
MIN
Trip-to-
Reset
Zone
Repeat-
ability
Single High-Low Unit
10
(1)
≤
1 5
≤
0 25
High-Only/Low-Only Pair
3
≤
1.5
≤
0.25
1. 5000 and 7500 psig Bourdon tubes are 15 percent of Bourdon tube rating.
Figure 6. Performance Characteristics
TRIP-TO-
RESET ZONE
SET POINT
∆
P
MIN
100%
OUTPUT
PRESSURE
PROCESS PRESSURE
A2897-2
7. Compare the pressure of the external pressure
source with the desired low set point setting.
8. If necessary adjust the low set point pressure by
turning the LOW SET knob (key 67) clockwise to
increase and counterclockwise to decrease the low
set point setting. Once the desired low set point is
achieved, rotate the locking arm to the locked
position.
Alignment of the Nozzle Beam
Perform this procedure before startup if the
self-aligning disk of the nozzle beam is noticeably
misaligned with respect to the nozzle area of the
block-and-bleed relay (see figures 7 and 8). Key
numbers are shown in figure 8.
1. Remove the case cover screw (key 5) and the
case cover (key 3).
2. Lift the end of the flapper off the nozzle beam
approximately 19 mm (0.75 inch) by moving the
opposite end of the flapper clockwise for a slight
rotation.
CAUTION
Be careful not to force the flapper such
that the spring (key 18) will become
damaged.
