6.1.2 Signal Test Board
The signal test board is used to test circuitry within the
adjustable frequency drive and provides easy access to test
points. Its use is described in the procedures where called
out. See
, for detailed pin
descriptions. Plug the signal test board into power card
connector MK 104.
130BX
66.10
Figure 6.1 Signal Test Board
6.2 Access to DC Bus
Many of the following test procedures require access to
the DC bus.
1
2
130BX470.10
Figure 6.2 Location of DC Bus Bars
1
(+) DC bus
2
(-) DC bus
Fasteners are M5 studs
Table 6.1 Legend to
Before performing any work:
-
Ensure that line power is disconnected.
-
Ensure that the motor is disconnected.
-
If there is a brake option, ensure that the brake
is disconnected.
-
If there is a load share/regeneration option,
ensure that it is disconnected.
WARNING
Touching electrical parts of the adjustable frequency
drive could be fatal even after the equipment has been
disconnected from AC power. Wait 20 minutes after the
power has been removed before touching any internal
components to ensure that the capacitors have fully
discharged. See the label on the front of the adjustable
frequency drive door for exact discharge times.
Before doing any work, ensure the DC bus capacitors have
discharged. Measure the DC bus using a voltage meter.
See
6.3 Static Test Procedures
6.3.1 Pre-check Precautions
Consider the following safety precautions before
performing static checks.
•
Prepare the work area according to the ESD
regulations.
•
Ground the ESD mat and wrist strap.
•
Ensure that the ground connection between
body, the ESD mat, and the adjustable frequency
drive is always present while performing service.
•
Handle disassembled electronic parts with care.
•
Perform the static test before powering up the
fault unit.
•
Perform static test after completing the repair
and assembly of the adjustable frequency drive.
•
Connect the adjustable frequency drive to line
power only after completion of static tests.
•
All necessary precautions for system startup must
be completed before applying power to
adjustable frequency drive.
Test Procedures
Service Manual
70
Danfoss A/S © Rev. 2014-02-10 All rights reserved.
MG94A222
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