Peter electronic VersiComb II 230-3, Installation And Commissioning Instructions

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VC II 230/400-3...15 17
10. Dimensioning of pre-fuses
The pre-fuses F can be dimensioned by means of the following instructions.
Basically, two types of fuse protection are available for the user.
1. Fusing according to allocation type „1“, DIN EN 60947-4-2.
After a short circuit, the device is allowed to be inoperative and repair work is possible.
2. Fusing according to allocation type „2“, DIN EN 60947-4-2.
After a short circuit, the device must be suitable for further use. However, there is the
danger that the contacts of the bypass or braking relays weld. Therefore, if posssible,
these contacts are to be checked prior to reconnecting the device to the mains supply. If
this check cannot be carried out by the user, the device has to be returned to the producer
in order to have it checked.
The following dimensioning information refers to the below operating conditions:
• Use of standard asynchronous motors
• Standard starting and/or braking times
• Switching frequency not excceding the value indicated in the data shee
Fusing according to allocation type „1“:
As pre-fuses, we recommend to use line protection fuses (utilization catgory gL) or automatic
circuit-breakers with type K tripping characteristic. In the case of automatic circuit-breakers, the
tripping characteristic of the type series is to be taken into account when protecting the soft start
section. With 2x I
n
the tripping time should be at least 20s (I
1
).
Taking into account the maximally occurring starting current (normally up to the 5-fold rated
device current of the starting section) and the maximally occurring braking current (normally the
rated device current of the braking section), we recommend fuse values according to table 1,
column 4 for the starting section, and column 5 for the braking section.
In the case of special devices having increased starting or braking times, the recommended fuse
value may have to be adapted.
Note: Wiring cross-sectional area according to DIN VDE 0100-430,
DIN EN 57100-430.