Bartington MAG-03PSU, Руководство по эксплуатации и техническому обслуживанию

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OM0065 ISSUE 5 PAGE 10 of 21
(ii) If it is believed that charging is not taking place connect a voltmeter across the
battery. Whilst charging is taking place the battery voltage should increase to 6.7 V.
(iii) If the battery voltage is not 6.7 V remove the power supply connector and check
for around 12-18 V (unregulated) between the outer and inner terminals of the connector. If this
is not present then the ac adaptor is suspect and a replacement should be sought.
(iv)
If the ac adaptor is believed to be working then the fault may exist in the regulator IC1 and
associated circuitry.
Suspect battery
If the battery voltage is 6.7 V under charge but is believed not to retain a charge carry out the
following test:-
Connect the 6.8ohm resistor and voltmeter simultaneously across the battery terminals. A battery
in reasonably good condition should sustain a voltage of 5.8 V minimum for five seconds. For an
older battery a voltage of 5.2 V minimum for five seconds should be expected. Failure to do so
indicates that a replacement battery is required.
Replacing the battery
(a)
Remove the three M3 nuts and shakeproof washers which retain PC36.
(b)
Separate the front and rear panels of the power supply unit (Do not disconnect any wires).
(c) Disconnect the battery terminals.
(d)
Prise the battery away from the base plate to which it is retained by two small pieces of
double sided adhesive tape.
(e)
Obtain a new part and install in the reverse order. Strictly observe that the positive
terminal with the red wire is connected to the switch and the negative terminal with the
black wire is connected to PC36.