ABB VT Guard Pro, Instructions For Installation, Use And Maintenance Manual

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6 1VLM000651, Rev.3, en 2014.01.21
The VT Guard-D has self-check functions. The status of the device is indicated by

Diodes, which are placed in such a way, that they are visible (only when activated) through unused holes at the
screw terminal holes on the right side, position 17 - RED, 18 –GREEN

Fig. 6.
LED indication
Description
RED GREEN
- Diagnostic power is OFF
X
- Diagnostic power is ON
- Device OK
X
- Diagnostic power is too low
- Circuit error occured
X X
- Diagnostic power is too low or
circuit error occured
a) OK b) internal failure
Fig. 6– Device status, LED position

Terminals X3:1 and X3:2 (see Fig. 4, Fig. 55). In case of proper operation, auxiliary contacts are switched on.
Superior system (e.g. protection relay - separate device with available binary inputs/outputs) sends and receives
the same signal through these terminals. In case of internal failure, there is no signal flowing through.
3. Installation
VT Guard Pro should be fitted in low-voltage compartment of the MV switchgear at the DIN – TS 35 rail
Fig. 77 in vertical position at least 20 cm from other thermal sources. Connection should be done according to the
Fig. 4 or Fig. 55 by insulated wires (minimum cross-section should be 1,5 mm2, maximum – 2,5 mm2). Max.
length of the connection wires up to 150 m. Minimum temperature wires rating is 75°C! The device should be
connected via switches /isolators (–FD1, -FD2) according to (Fig. 22, Fig. 4, Fig. 55) to meet IEC 61010-1 (CE
marking). If the switches/isolators are not used it has no impact on the device functionality. The device contains self-
protection components which disconnect device in case of internal failure.

functional (terminals X1:1, X1:2)….-FD1,resistive load AC1, min 15A tripping ability, recommended device -
ABB isolator E202

diagnostic (terminals X2:1, X2:2, X2:3)…-FD2, resistive load AC1, min 1A tripping ability, recommended device -
ABB isolator E203
The switches shall be in close proximity to the device and within
easy reach or an operator.
The switches shall be marked as the disconnecting device for the
equipment.