SM 1690
page 16 of 18
File: SM1690_r5eng - Dec. 2013 - Technical note: SM1690
SM 1690
SM 1280
SM 1690
File: SM1690_r5eng - Dec. 2013 - Technical note: SM1690
page 17 of 18
ALARM TROUBLESHOOTING
Code
Description
Cause/Solution
01
Magnetron Over
Temperature
a) Check water flow and incoming water temperature
b) Check magnetron thermoswitch (contact grounded=OK,
open=alarm)
c) Check setting of magnetron thermocouple: if latter isn’t
present the alarm threshold must be set = 0
d) Check air flow.
e) Excess of reverse power. Reduce power,
02
Rack Over
Temperature
a) Check for restrictions to the air flow
b) Eliminate air recirculating between outlet on the sides and the
rear inlet
03
Arc Detected
Electric arc in waveguide.
If arc detector isn’t used, the related input must be grounded.
If used, contact grounded=OK, open=alarm
On alarm, check waveguide and magnetron antenna status.
Check Arc detector wiring.
04
Over Current
An excessive current has been detected, or a dangerous
temperature is present into the unit.
a) Check air flow blocks.
b) Eliminate air reflow between side entry and rear output.
c) A short circuit is present on H.V. cable: check wiring.
05
Over Voltage
a) The high voltage connection is open
b) Magnetron may be moding
c) The high voltage connectors are not fully inserted: if true
check for h.v. spot discharge inside socket/plug: in case replace
them.
d) The filament is cold: check filament current with high voltage
OFF (=enable signal OFF, h.v. connector #3 disconnected)
Check filament transformer wiring and compliance.
e) Verify preheating timer checking how many seconds require
the “READY” led to become ON stable: if you feel too short try
to enable the unit (= enable MW ON) only 10 seconds after
enabling the filament (if the command is available) or after
general power ON (when the filament command is always ON)
f) check the filament timer (with the FrontPanel program from the
PC): set >10 seconds.
