BENSHAW RediStart MX3 Series, User Manual

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Step 6
8.6.2
Powered BIST Tests
(FUN 22 - Powered BIST):
The powered BIST tests are designed to be run with normal line voltage applied to the starter and a motor connected. Powered BIST
verifies that the power poles are good, no ground faults exist, CTs are connected and positioned correctly and that the motor is
connected. Powered BIST mode can be entered by entering the appropriate value into the Miscellaneous Command (FUN22) user
parameter.
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NOTE: The powered BIST test is only for use with SCR based reduced voltage soft starters. Powered BIST can not be used with
wye-delta or ATL types of starters.
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NOTE:
The motor wiring MUST be fully connected before starting the powered BIST tests. Also the motor must be at rest
(stopped). Otherwise the powered BIST tests will not function correctly.
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NOTE: Before using the powered BIST test function, the following MX
3
user parameters MUST be set for correct operation of the
powered BIST test: Motor FLA (QST01), CT Ratio (FUN03), Phase Order (FUN04), Rated Voltage (FUN05), and Starter Type
(FUN07).
The powered BIST tests comprise of:
Step 1 LCD Display
Go to FUN22- misc commands and press [ENTER].
Increment up to "Powered BIST" and press [ENTER].
Powered BIST test will commence.
Step 2– Shorted SCR and Ground Fault Test:
In this test each power pole is energized individually. If current flow is detected, the MX
3
controller attempts to differentiate whether it
is a shorted SCR/shorted power pole condition or a ground fault condition and either a “Bad SCR Fault” or “Ground Fault” will occur.
Step 3– Open SCR and Current Transformer (CT) Test
In this test, a low-level closed-loop controlled current is selectively applied to various motor phases to verify that the motor is connected,
all SCRs are turning on properly, and that the CTs are wired and positioned properly. If current is detected on the wrong phase then a
“BIST CT Fault” fault will be declared. If an open motor lead, open SCR, or non-firing SCR is detected then a “Bad SCR Fault” will
occur.
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NOTE: When this test is in progress audible humming or buzzing maybe heard from the motor.
Pressing [ENTER] on the keypad at any time will abort the current test in progress and proceed to the next BIST test.
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NOTE
: If line voltage is lost during the powered tests a “BIST Abnormal Exit” fault will occur.
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NOTE:
The powered BIST tests will verify that the input phase order is correct. If the measured phase order is not the same as the
Phase Order (FUN04) parameter a phase order fault will occur.
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8 - TROUBLESHOOTING & MAINTENANCE
BIST Mode
Tests completed
FUN: Misc commands
22
Powered BIST
BIST Mode
Shorted SCR/GF
BIST Mode
Open SCR/CTs