720A Operation and Maintenance Manual – Rev S – January 25, 2019
Page 22
13231 Rooster Springs Rd.,
Austin, TX 78737
T:
(512) 858-4045
E:
amptec.com
E-3 Basic Troubleshooting
The following section will assist you in diagnosing simple problems with your 720A
meter. While there are a few common errors that can be resolved by the end user, it is
often recommended that you send your unit back to AMPTEC’s facility for further
evaluation/repair. If in doubt simply contact us to set up the evaluation of your unit - our
trained staff can quickly diagnose the problem and provide you with a simple solution.
For more information on how to send your product in to our facility for evaluation and
repair, please see section E-2 on the previous page.
Problem:
720A meter will not turn after the on/off switch has been
flipped into the “ON” position.
Possible Solutions:
A.
Make sure the batteries (if any) are charged and that
the correct charger/power supply is being used to
power the meter. The 720A can be powered by either
batteries or AC line voltage, depending upon the
options purchased.
B.
Ensure that the outlet being used to charge the
batteries/power the unit is in proper working order. If
your outlet has a “reset” button, try pressing it and see
if the unit will then respond.
C.
Check that the external fuse on the rear panel is still
intact. Unscrew the fuse holder on the unit’s rear
panel and visually inspect the fuse inside. A blown
fuse will need to be replaced but can be done so by
the end user with any compatible 3AG, 2A fuse.
Problem:
720A meter will not turn on after completing steps A, B, & C.
Possible Solutions:
D.
Further evaluation may be completed by opening up
your 720A meter. The meter’s case may be opened
by first unscrewing the screws on the bottom plate of
the unit inside the unit’s feet. Please note that any
opening of a 720A will void its warranty and
calibration (if applicable). It is highly recommended
that an ESD bracelet or equivalent static discharge
instrument is worm any time the circuit board of a
720A meter is being touched.
E.
If you have a battery powered 720A meter, check that
the batteries of the meter have not been dislodged. If
the unit has been dropped or handled very roughly
during shipping, it is possible that the batteries shifted
and/or dislodged, causing the 720A meter to not
function properly.
F.
Check that the circuit board at the front of the meter
that contains the LED display digits is still plugged
