7
Switzer operating instructions pressure switch, model PS01-W1.
O
I-P
S
0
1
-W
1
1
1
/2
0
1
6
5. Procedure
Fixed on-off diff erential models
a) Rotate the range adjustment screw clockwise to increase the switching point.
Rotating anti-clockwise will decrease the switching point.
b) After setting, r
e-fi x the locking device back in position to prevent unauthorised
adjustment of the setpoint.
c) The center screw and the striker screw are precisely adjusted and factory-set
using thread lock sealant. Alteration of centre screw height will disturb the contact
established between the sensor and the balance beam. Disturbance of striker screw
will result in microswitch not acting properly or result in setpoint shift.
Sensing of switching points
Fix the instrument on to a calibrator setup with a master gauge of accuracy better than
1% to set the actuation point.
Setpoint should be preferably in the mid of the adjustable range span.
Adjustable on-off diff erential models
On-off diff erential value can be adjusted for a wider value from about 10 to 15% of the
FSR to a maximum of 60% as specifi ed against each range. The minimum value will
vary with diff erent switch combinations. This adjustment is achieved by an auxiliary
spring brought into action when the switch actuating plate moves up before it operates
the microswitch. Adjustment of the load of the spring decides the pressure diff erence
between the on point and off point.
Range screw
Range scale Index
Striker screw
Fig.2
