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NO. FAILURE CAUSE TREATMENT
5 Fluctuant flow rate 5.1 Inlet pressure is too low or
instable
Heighten inlet pressure
5.2. High internal gas resistance Lessen internal resistance (The heavy
gas flow should have big valve open,
widen tube to parallel connecting gas
bottles to improve gas supply capacity.)
5.3 Circuit or valve failure *Repair and adjust
6 Disturbed by high
frequency power
sourcing
6.1 Earth wire and zero wire
connecting of power supply is error
Check the earth wire connection, should
be one port connection.
6.2 Signal reference port connecting
problem
Check signal connecting wire.
6.3 Inter space disturbing
7 Flow display is in-
accurate
7.1 The range or unit of Display is not
matching to controller.
*Re-adjust Display
7.2 Bypass is polluted to cause the
flow rate excursion.
*Clean MFC and re-calibrate it
7.3 Zero excursion happened to be
instable.
* Change sensor and repair circuit
8 There is still flow
passing while zero
setting.
8.1 Valves leakage *Repair solenoid control valve
8.2 Zero point is moving less than 0 Adjust zero
9 The heavy flow is
passing but no
outputting display
9.1 Block of sensor *Repair and replace the new sensor
Should add filter to block gas dust.
Using special gas should be sure of
good tube sealing and gas dryness.
9.2 Circuit failure *Repair circuit
10 Without gas flow, Zero
is fluctuate or
excursion happened.
10.1 Sensor failure *Replace a new sensor
Attention
:
* Mark indicates that reparation and adjustment must be dealt under specialist advices。