
B-70255EN/01 9.SETTING AND ADJUSTMENT
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9.7 WATER FLOW SENSOR
This sensor is precisely adjusted at the factory and should not require
any further adjustment. If the water distribution unit or water flow
sensor is replaced, however, this sensor should be set and adjusted as
described below:
9.7.1 Adjusting the Water Flow Sensor
The operation point of the water flow sensor for C1000iA depends on
the pressure at the cooling water inlet of the oscillator.
So, note that the alarm operation point may slightly shift if the length
of piping from the chiller is changed significantly for a cause such as
the movement of the oscillator.
The adjustment method described below assumes that the pressure at
the cooling water inlet of the oscillator is 0.36 to 0.50 MPa.
(1) Detach the water flow sensor cables (black, white) from the
terminal block, then connect a tester to the tips (Faston
terminals). Set the tester for the resistance measurement range or
conduction check range.
(2) Adjust the flow rate the cooling water entering the oscillator to a
predetermined alarm flow rate. To perform this adjustment, use a
flowmeter having an appropriate capacity and accuracy.
Model Predetermined alarm
flow rate
Rated flow rate
C1000iA
32 liters/min 40liters/min
(3) Remove the packing at the top of the water flow sensor, then
adjust the flow rate setting screw to find the position where the
flow rate sensor is placed in the conduction state (on).
(4) From the found position, turn the flow rate setting screw of the
water flow sensor counterclockwise until the water flow sensor
just becomes off.
(5) Increase the cooling water flow rate gradually to the alarm-off
setting flow rate, then check that the water flow sensor is on.
Model Alarm-off setting flow rate
C1000iA
35 liters/min
(6) Close the valve and make an adjustment to the alarm setting flow
rate, then check that the water flow sensor is off.