9
Switzer operating instructions pressure switch, model PS01-W1.
O
I-P
S
0
1
-W
1
1
1
/2
0
1
6
Procedure Contd.,
Notes
1) In the instruments with 2 SPDT switches for DPDT action, the synchronization of
actuation is achieved within practical limits.The switches are synchronized as per
customer preference either on falling or on rising pressure. If no preference is
indicated, synchronization is done on fall in pressure at factory.
2) ON & OFF set point should not exceed the upper or lower range of scale value
3) Ensure that impulse pipework applies no stress on sensing element housing and use
spanners to hold pressure port/ housing when connections are made.
4) Use the instrument only f
or the medium specifi ed.
e)
Precaution:
The switch actuating screw on the balancing arm is critically
adjusted. Disturbance of this would result in malfunctioning while on-off diff erential
adjustments are made. If accidentally disturbed, to reset microswitch adjust the
striker screw height such that the balancing arm is not in contact with auxillary
spring seat during switch de-actuation thereby ensuring that the auxillary spring
remains unloaded during de-actuation. Refer Fig.3.
For actuation of the microswitch, the balance beam has to lift the aux. spring seat
which is pre-loaded with the desired value of wide band On -Point. Ref Fig.4
Fig.3 : Switch at ‘off’ position Aux
spring load not acting
Fig.4 : Switch at ‘on’ position Aux
spring load acting
0.5/0.8 mm gap
Aux. spring
Aux. Spring seat
Microswitch
Microswitch
Aux. spring seat
Aux. spring
