Thermal Dynamics PAK Master 150XL, Руководство по обслуживанию

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Manual 0-2728 4-13 SERVICE TROUBLESHOOTING
4. Pull the top of the Side Panel out and then lift up to
remove the panel from the Power Supply a short dis-
tance (see NOTE).
NOTE
There is a ground wire connection to the Side Panel
on the inside of the unit.
5. Remove the nut securing the ground wire to the side
panel and remove the ground wire.
6. Remove Side Panel from unit and set aside.
7. Reinstall the Side Panel by reversing the above proce-
dure and doing the following:
a. Reconnect the ground wire to the Side Panel, if
disconnected.
b. Place the Side Panel onto the frame and slide the
top edge under the lip on the Top Panel.
c. Reinstall all the screws to secure the Side Panel.
C. Diode Testing Basics
Testing of diode modules requires a digital volt/ohmme-
ter that has a diode test scale. Remember that even if the
diode module checks good, it may still be bad. If in doubt,
replace the diode module.
1. Locate the diode module to be tested.
2. Remove cables from mounting studs on diodes to iso-
late the module.
3. Set digital volt/ohmmeter to diode test scale.
4. Using the Figures for each test, check each diode in
the module. Each diode must be checked in forward
bias (plus to negative) and reverse bias (negative to
plus) direction.
5. Connect the volt/ohmmeter positive lead to the an-
ode (+) of the diode and the negative lead to the cath-
ode (-) of the diode for forward bias testing (refer to
following figure). A properly functioning diode will
conduct in the forward bias direction and indicate be-
tween 0.3 to 0.9 volts.
0.75
VR COM A
A-00307
Anode
Cathode
Forward Bias
Diode Conducting
+
_
Diode Test Symbol
Testing Diode Forward Bias
6. Reverse the meter leads across the diode for reverse
bias testing (refer to following figure). A properly
functioning diode will block in the reverse bias direc-
tion and depending on the meter function will indi-
cate an open or “OL”.
OL
VR COM A
A-00306
Anode
Cathode
Reverse Bias
Diode Not Conducting
+
_
Testing Diode Reverse Bias
7. If a diode checks bad, replace the diode module.
8. Reconnect all cables to proper terminals.