2024-01-24
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INSTRUCTION MANUAL
ISL-A 24/ ISL-A 48
DEVICE FOR INSULATION PERMANENT CONTROL FOR ISOLATED NETWORKS (IT)
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GENERAL
In IT electrical distribution networks with isolated neutral, the high insulation impedance prevents earth faults
from generating currents that would dangerously elevate the potential of exposed conductive parts.
Therefore, in case of earth leakage in an IT network, it is not necessary to interrupt the supply, but it is still
essential to continually monitor the insulation level in order to detect faults and restore optimal functioning
of the system.
The ISL-C 230 is an Insulation Monitoring Device for IT networks with voltages of 24 to 48 V ac/dc. These de-
vices measure the potential variation of two polarities in reference to earth, to signal when the insulation is
decreasing below a fixed value.
Auxiliary supply is taken from the under-control network. On the front panel, there is signaling for the device
being ON, TEST and RESET push-buttons, and three LEDs for signaling a tripping (TRIP) and to indicate the
polarity of the line under control that has low insulation.
The threshold for trip is regulated by a series of micro-switches. There is a changeover contact relay available
to transfer the information of the low insulation signaling to a remote panel.
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INSTALLATION
The installation must be carried out by qualified and authorized personnel and in the absence of voltage.
Make sure that the instrument is O.K. and has not been damaged during transport.
Make sure that the voltage supply is compatible with the operating voltage of the instrument.
For each independent line, it's possible to use only one control device.
The device is a 3 modules (17.5mm) DIN version with snap on 35mm DIN rail.
It has a sealable transparent front protection cover.
The green LED ON will light up after the connections are set and the instrument is powered on.
DESCRIPTION
1.
Green LED ON, signaling the instrument is working.
2.
Red LED TRIP, signaling a trip for low insulation; in manual reset
mode, it is necessary to press the RESET to cancel the signaling.
3.
Red LED TRIP (+ / -), in low insulation status, signals the polarity
under the trip threshold in a direct line, while both LEDs will be on in
an alternating line, functioning in automatic reset.
4.
TEST button to test the instrument's functionality.
5.
RESET button to cancel the trip signaling (manual reset).
6.
Micro-switches to select the threshold for trip.
