BCD.00617 Rev AB,16-Nov-2015

Page 13 of 15

MELCHER

The Power Partners.

Accessories Data Sheet

Backplanes BPD, BPF for T Series

• Double or reinforced insulation between input and output,

based on 250 VAC

• Operational insulation between output and earth

• The use in a pollution degree 2 environment

• Connecting the input to a primary circuit with a maximum

transient rating of 2500 V (overvoltage class III based on a

110 V primary circuit, overvoltage class II based on a 230 V

primary circuit).

Troubleshooting

See also: T Series converters data sheet Functional Features.

• All T Series converters are operating, all Sys OK LEDs are

OFF.

– Sys In is not referenced to Vo–

• 3-phase AC input, Y-configuration. One T unit indicates

Error.

– single T unit failure or

– single T unit inhibit or

– single phase mains failure

• All System OK LEDs are OFF, all T units indicate Error.

– mains failure or

– all T units inhibited, e.g. battery test or less likely

– all T units have a failure

• The red Error LED of one of the T units is ON.

– T unit with Error LED ON has an overtemperature, the

output is automatically re-enabled when the temperature

drops below the limit.

• The red Error LED flickers.

– overvoltage disturbance from the mains.

• One of the T units has all LEDs OFF.

– short circuit across output of a T unit.

• All Sys OK LEDs ON, at one T unit the Uo OK LED is ON.

The remaining T unit are below the threshold level of the

power down signal with the LED Uo OK OFF.

– a fuse on the back plane damaged, relevant T unit

with Uo OK ON.

• All LEDs at the T units are OFF, mains is apparent.

– short circuit across the power bus

• Single phase AC input. Only one T unit is in operation.

– wire jumpers on mains input connector X1 not con-

nected to L2/ L3 input terminals

• All Sys Good and Uo OK LEDs are ON, no output power.

– output not connected to the system

• All T units are operating. One or several T units indicate

Error with the Uo OK LEDs OFF although the bus voltage is

present.

– Dset not referenced to Vo+

Isolation

The electric strength test is performed in the factory as routine

test in accordance with IEC/EN 60950 and EN 50514.

Important: The backplane must carry the safety covers,

which prevent from touching conductive parts. Such covers

are mounted on both sides of the printed circuit board and over

the bus bars. Removing the protection covers will provoke

danger of high voltage or high energy impact! Testing by

applying AC voltages will result in high and dangerous leakage

currents flowing through the Y-capacitors (see fig. Block

diagram of back plane).

Table 6: Isolation

Characteristic

Input to

Input to

Output to

Unit

earth

output

earth

Electric

Required according to

1.5

3.0

0.5

kVAC

strength

IEC/EN 60950

2.1

4.2

0.7

kV DC

test voltage

Actual factory test 1 s

2.8

4.2

1.4

AC test voltage equivalent

2.0

3.0

1.0

kVAC

to actual factory test

Insulation resistance at 500 VDC

>300

>300

>300

M

Ω