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MS220Vi and MSR220Vi
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14.3 Wiring
The lines of the sensor circuit are to be routed as separate control lines. The use of lines of the supply cable or
other mainstream lines is not permissible. If extreme inductive or capacitive stray effects are to be expected by
parallel cables of the power installation, shielded control lines should be used. Recommendations for intrinsic
safety protection should be observed.
For devices type MSR the terminals Y1, Y2 may be attached parallel to a common resetting mechanism. Sensor
lines may not be connected together.
The line resistance within the sensor circuit may not exceed a value of 20 Ω.
Maximum of permissible length for sensor circuit lines:
Wire cross section
Wire length
2,5 mm
2
2 x 500 m
1,5 mm
2
2 x 400 m
1,0 mm
2
2 x 250 m
0,75 mm
2
2 x 150 m
0,5 mm
2
2 x 100 m
With commissioning and after modification of the plant the sensor resistance must be checked with a suitable
measuring instrument. With a resistance < 50 Ω the sensor circuit is to be examined for short-circuit.
Attention! Check PTCs only with measuring voltages of < 2.5 V
.
14.4 Safe Separation
Mains supply circuits (A1, A2 in devices with transformer), (11, 12, 14 and 21, 22, 24) have safe separation to
low-voltage electric circuit (Y1, Y2) as well as to the intrinsically safe circuit (T1, T2).
Tripping devices with combined supply voltage DC/AC 24 V have no potential separation and are only permitted
with power supplies that comply with the requirements of EN 61558 / DIN VDE 0551 (safety transformer or
battery power) and when protected wiring is used. Caution! Supply voltage AC 24 V must not be grounded to
earth (PA).
14.5 Stop function
A stop function released by the protection device must transfer the machine after manipulation of this function
as fast as possible into a safe condition. The stop function must have top priority.
In case of failure the relay switches off the contactor/circuit breaker and so prevents an overheating of the
isolation system and/or the surface temperature. The protective function of the equipment is guaranteed only
if wiring is done directly into the control circuit of the motor/machine in accordance with the connection
diagram. The contacts must be protected, in order to prevent welding.
Attention!
The relay contacts must be fused externally to prevent welding of the
contacts. Recommended fuses see technical data.
14.6 Start and Restart
A restart may take place automatically only if no dangerous condition can be present. The tripping devices of
types MS 220 Vi are equipped with an automatic reset function. For this device design, suitable wiring of the
control units must be ensured to prevent automatic restarting of the explosive-protected motor of the type of
protection Increased Safety „e“ in case of failure.
14.7 Manual resetting
After introducing a stop instruction by the protection device this must be maintained, until the manual resetting
mechanism is operated and safe conditions for a renewed start are given. The manual resetting may be only
possible, if all safety functions and protection devices are effective.
Trip device type MSR has an electronic reclosing lock. The stop instruction remains, until pressing the push-