Honeywell MP-953D User Manual

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9
,$$ AREPAIR AND ADJUSTMENT PROCEDURES FOR HONEYWELL MP-953B, MP-953D,
lb
MP-953P PNEUMATIC OPERATORS USED ON ARMSTRONG HUMIDIFIERS
x.
Feedback springs are available in a kit containing:
l- Bias Spring
l-
White feedback spring, operating range 3 psi
1 - Bronze feedback spring, operating range 5 psi
1 - Violet feedback spring, operating range 10 psi
3.
To change the feedback spring:
:;
Turn off the instrument air.
Remove the pilot positioner by removing the two
phillips head screws and one cover screw.
Do not
remove the pneumatic tubing.
c)
The feedback spring is located in the operator on
top of the main diaphragm.
Remove the old
feedback spring.
d)
Insert
the feedback spring that will give the
desired operating range.
Replace the bias spring
located on top of the operator.
e)
Replace
the pilot positioner.
f)
Turn on the instrument air.
ADJUSTMENT CHECK
(MP-953B AND MP-953F MODELS ONLY)
1.
Install guages in the main and pilot air lines.
2. Main air pressure should be equal to or more than top
of sequencing range: 13 psi is minimum main pressure
for device to function.
3. Slowly apply pilot pressure and note the pressure at
which valve stem travel starts.
This pressure should
be within + 3/4 psi for the B model (+ 1 psi for the F
model) of the start point setting.
4. Slowly increase pilot pressure until valve stem travel
is complete. This pressure should be within + 3/4 psi
for the B model (+lpsi for the F model) of the start
point pressure plus the range setting.
5 Make fine adjustments, if necessary, with the start
point adjustment knob.
CAUTION (B MODEL ONLY): Loosen
the cover locking screws before turning the start point
adjustment knob.

Honeywell MP-953D Specifications

General

Brand	Honeywell
Model	MP-953D
Category	Controller
Language	English