Mitsubishi Electric NF250-HEV, Instruction Manual

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4
2.2 Withstand voltage test
● When conducting a MDU terminal test, always connect the MDU Breaker main unit and MDU.
● A voltage measurement transformer is connected between poles on the load side of the MDU Breaker main unit.
In the table below,
×
indicates that, because it causes a failure, withstand voltage test between poles on the load side must not be performed.
In the table below, △ indicates that, although nothing broke during a 500 VDC insulation resistance test, there was a low insulation resistance value.
No problems found during withstand voltage test and insulation resistance test conducted on entire main circuit and between ground on MDU
Breaker main unit.
● When checking DA, DB, DG, 485+, 485-, Ter, SLD, and FG terminal conductivity for models with CC-Link communication/MODBUS communication,
do not allow the voltage between each terminal to reach 5 VDC or higher.
Doing so may cause failure.
*1. Test with MDU terminals (L1, L2, 114, 113, DA, DB, DG, 485+, 485-, Ter, SLD, FG) as ground side.
*2. Test with MDU terminals (114, 113, DA, DB, DG, 485+, 485-, Ter, SLD, FG) as ground side.
*3. Do not perform a withstand voltage test between MDU terminals (DA, DB, DG, SLD) and MDU terminal (FG).
*4. MDU terminals (DA, DB, DG, SLD, FG) must always be tested together.
*5. Do not perform a withstand voltage test between MDU terminals (485+, 485-, Ter, SLD) and MDU terminal (FG).
*6. MDU terminals (485+, 485-, Ter, SLD, FG) must always be tested together.
Measurement point/test
Between MDU terminals (L1, L2) and MDU terminals (DA, DB, DG, SLD, FG) (with CC-Link
communication) (*3) (*4)
Insulation resistance
measurement
ON OFF
Withstand voltage test
ON OFF Test conditions
〇 〇
〇 〇
〇 〇
〇 〇
〇 〇
〇 〇
〇 〇
〇
〇
〇
〇
〇 △
△
△
△
△
△
△ △
△ △
△ △
〇
〇
〇
〇
〇
〇
〇
〇
〇
〇
〇
〇
×
×
×
×
〇
〇
Between MDU terminals (L1, L2) and MDU terminals (485+, 485-, Ter, SLD, FG)
(with MODBUS communication) (*5) (*6)
〇 〇 〇 〇
〇
〇
〇
〇 〇 〇 〇
〇
〇
×
×
×
×
×
×
×
×
– –
Status of handle
Between live part and ground
Between main circuit and MDU terminals (L1, L2, FG)
Between power supply and load terminal
Between main circuit and MDU terminals (114, 113, FG) (with electric energy pulse output)
Between main circuit and MDU terminals (DA, DB, DG, SLD, FG) (with CC-Link
communication) (*4)
Between main circuit and MDU terminals (485+, 485-, Ter, SLD, FG) (with MODBUS
communication) (*6)
Between MDU terminals (L1, L2) and MDU terminal (FG)
Between MDU terminals (L1, L2) and MDU terminals (114, 113, FG) (with electric energy
pulse output)
Between different
poles
Line side
Load side
Between left and middle poles
Between middle and right poles
Between left and right poles
Between left and neutral poles,
Between middle and neutral poles,
Between right and neutral poles
(for a four-poles circuit breaker)
Between left and middle poles
Between middle and right poles
Between left and right poles
Between left and neutral poles,
Between middle and neutral poles,
Between right and neutral poles
(for a four-poles circuit breaker)
2500 VAC
1 min.
2500 VAC
1 min. (*1)
1500 VAC
1 min. (*2)
Caution