Open Circuit Conditions Or No Supply Voltage; Short Circuit Conditions - Bartington MAG-03PSU Operation & Maintenance Manual

13.2 OPEN CIRCUIT CONDITIONS OR NO SUPPLY VOLTAGE

Ensure that power is supplied to the magnetic field sensor. Remove the cover of the Mag-03PSU
power supply unit and establish that a voltage of ±12 to ±13 V is obtained on Pins 5 and 7
respectively relative to pin 6 on PC36 with the unit switched on. If the supply voltage exists then
complete the following tests. If not go to Section 13.4
(i) If the cable is suspected then the power should be switched off, the cable removed
and a continuity tester used to discover any breaks in the cable conductors.
(ii) If no breaks are discovered then the magnetic field sensor module should be
suspected and returned for replacement or repair.

13.3 SHORT CIRCUIT CONDITIONS

If the Mag-03PSU power supply is connected to a magnetic field sensor, excessive current drain
will be indicated by overheating of IC2.
(i) To eliminate the magnetic field sensor, switch off and disconnect it then switch on
and see if the condition persists.
(ii) To eliminate the cable, disconnect it and see if the condition persists.
(iii) If the condition still exists then the voltage converting and filtering circuitry should be
suspected.
(iv) If the cable is suspected, use a continuity tester to check for short circuits.
(v) If the magnetic field sensor is suspected, please return it for repair.
(vi) If the circuitry within the power supply is suspected, further tests using the DMM
may be carried out.
13.4 BATTERY
WARNING: The battery is of the fully sealed lead acid type and can deliver current in excess of
40 A. Do not under any circumstances short circuit the battery.
Suspect charger
If the power supply unit does not produce a ±12 to ±13 V supply check that the battery is fully
charged. If it is then the voltage converter IC3 should be suspected. If the battery is not charged
carry out the following tests:-
(i) Connect the ac mains adaptor to the power supply and leave on for at least ten
minutes with the Mag-03PSU switch in the down or OFF position. If the mains adaptor and
battery charger circuitry is functioning the power supply will become slightly warm and the
constant voltage regulator IC1 which is mounted on the front panel using an insulation washer will
become hot (Take Care).
OM0065 ISSUE 5 PAGE 9 of 21