NORD Drivesystems BU0230 - Manual (Page 46)

Functional safety with NORD SK 200E frequency inverters
46 BU 0230 GB-2712
Spitzenstrom (ohne Belastung von DO1)
0A
1A
2A
3A
4A
5A
0,0Ω 0,5Ω 1,0Ω 1,5Ω 2,0Ω 2,5Ω 3,0Ω
Leitungswiderstand
21,6V
24,0V
30,0V
Spitzenstrom (DO1 mit 200mA belastet)
0A
1A
2A
3A
4A
5A
6A
7A
0,0Ω 0,5Ω 1,0Ω 1,5Ω 2,0Ω 2,5Ω 3,0Ω
Leitungswiderstand
21,6V
24,0V
30,0V
This current only occurs for a short time after a test pulse from an upstream protective switching device and
reduces according to the DC resistance of the cable used. Care should be taken that both the protective
switching device (with OSSD) and the feed source can withstand this current.
3.6.3 Multi-device operation
For devices with two 24V and two GND terminals (Terminals 44 and 40) the cables can be looped through the
terminals up to a total current of 6 A. For larger total currents, the two conductors (incoming and outgoing)
must be clamped under a single terminal (if necessary with TWIN wire end sleeves).
When operating several inverters on one protective switching device, the switching capacity of the switching
device and the load rating of the 24 V power-feeding supply must be observed.
The shield must be applied to all inverters.
The permissible line drops on the cable must be observed!
Example:
o 6 frequency inverters at an electronic protective switching device!
o The 6 inverters are directly adjacent to each other.
o 20 m must be bridged between the FI and the switching device!
o Shielded cable 2x1.5 mm
2
Peak current (without load from DO1)
Cable resistance
Peak current (DO1 with load of 200mA)
Cable resistance