6 Test Procedures
6.1 Introduction
WARNING
Touching electrical parts of frequency converter may be
fatal even after equipment has been disconnected from AC
power. Wait 40 minutes after power has been removed
before touching any internal components to ensure that
capacitors have fully discharged.
This section contains detailed procedures for testing F
Frame and 12-pulse series frequency converters. Previous
sections of this manual provide symptoms, alarms and
other conditions which require additional test procedures
to further diagnose the frequency converter. The results of
these tests indicate the appropriate repair actions. Again,
because the frequency converter monitors input and
output signals, motor conditions, AC and DC power and
other functions, the source of fault conditions may exist
outside of the frequency converter itself. Testing described
here will isolate many of these conditions as well. The
Disassembly and Assembly Instructions describe detailed
procedures for removing and replacing components, as
required.
Frequency converter testing is divided into
Static Tests
,
Dynamic Tests
, and
Initial Start Up or After Repair Frequency
Converter Tests
. Static tests are conducted without power
applied to the frequency converter. The purpose of static
testing is to check for shorted power components. Most
frequency converter problems can be diagnosed simply
with these tests. Static tests are performed with little or no
disassembly. Perform these tests on any unit suspected of
containing faulty power components prior to applying
power.
WARNING
Use extreme caution when conducting tests on a powered
frequency converter. For dynamic test procedures, main
input power is required. All line powered devices and
power supplies are energized at rated voltage. Contact
with powered components could result in electrical shock
and personal injury.
Dynamic tests are performed with power applied to the
frequency converter. Dynamic testing traces signal circuitry
to isolate faulty components.
Replace any defective component and retest the frequency
converter with the new component before applying power
to the frequency converter as described in
Initial Start Up
or After Repair frequency converter Tests
.
6.1.1 Tools Required for Testing
Metric socket set
7–19 mm
Socket extensions
100 mm–150 mm (4 in and 6 in)
Torx driver set
T10 - T50
Torque wrench
0.675–19 Nm (6–170 in-lbs)
Needle nose pliers
Magnetic sockets
Ratchet
Screwdrivers
Standard and Philips
Additional Tools Recommended for Testing
Digital volt/ohmmeter (must be rated for 1200 VDC for 690 V units)
Analog voltmeter
Oscilloscope
Clamp-on style ammeter
Test cable p/n 176F8766
Signal test board p/n 176F8437
Power supply: 610 - 800 VDC, 250 mA to supply external power to 4
power cards and the control card.
Power supply : 24 VDC, 2 A for external 24 V power supply.
6.1.2 Signal Test Board
The signal test board can be used to test circuitry within
the frequency converter and provides easy access to test
points. The test board plugs into the top of the modules.
Its use is described in the procedures where called out. See
Section 9, Signal Test Board, for detailed pin descriptions.
130BX
66.10
Illustration 6.1 Signal test board
6.2 Static Test Procedures
All static tests should be made with a meter capable of
testing diodes. Use a digital volt/ohm meter (VOM) set on
the diode scale or an analog ohmmeter set on Rx100 scale.
Before making any checks disconnect all input, motor and
brake resistor connections.
Test Procedures
High Power Service Manual for Modular F Frame Drives
MG90K202 - VLT
®
is a registered Danfoss trademark
85
6
6
