MKS 647C - Trouble Shooting

5. Application of the 647C 647C
42
5.2 Trouble Shooting
Symptom Possible Causes and Remedies
1. No display.
2. Display of gas flow
is close to zero or not
correct.
3. Display of gas flow
is on for a short time
and goes back to zero.
4. There are periodical
peak pulses at constant
gas flow.
5. Entering data is not
possible or there are
unreadable characters on
the display
Power Failure
- Wrong position of voltage
selector switch.
- Loose mains connection.
- No power in the outlet
– Fuse is defective
– Power supply is broken.
- Loose connecton.
– Power supply is broken.
– Mass flow controller is
warming up.
– Set point is not being
transmitted.
– Valve in the supply line is
closed.
Defect in the pipe line system.
– Supply line valve is closed.
– Pressure is down (check gas
supply).
– No differential pressure (e.g.
pump is turned off).
- Pressure regulator is defect,
(frequent defect, varying
supply pressure may help.
It is recommended to replace
the pressure regulator)
– Disturbance by external sources
(change the path of power
lines, sreen sources of
disturbance).
– There is probably iconsistent
data in battery backuped RAM.
The First Start Reset will fix
this problem.
If the trouble is limited to a part of the eight possible channels, it is recommended to localize the
source of trouble by exchanging mass flow controllers and their connecting cables.
In any case check the setup of the device.