ALTER SM1150, Technical Note

Page: 28 / 30

page 26 of 29
File: SM1150_r5eng - February 2007 - Technical note: SM1150
SM 1150
File: SM1150_r5eng - February 2007 - Technical note: SM 1150
page 27 of 29
SM 1150
ALARM CODES TABLE
Alarm Code Description Cause/Solution
MAGN 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,
TEMP 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
c) If you are using the “current control mode” limit the output at
750 mA
ARC 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.
CURR 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) In “Current control” mode, limit output current to 950mA
maximum.
d) A short circuit is present on H.V. cable: check wiring.
VOLT 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.