The digitally controlled MCM161x series monitors insulation level
between a non-grounded (IT) AC mains and its protective earth,
regardless of whether the mains is live or non-live (standby).
An AC or DC auxiliary voltage is required for the unit, if powered from a
separate source the network can also be monitored during standby
conditions. Only ONE MCM161x can be connected to each IT-system.
The
optional slave indicator give at a glance the clear safety message:
IDV MEASURING PRINCIPLE
Insulation is measured between the complete galvanically
interconnected AC network and its protective earth. The unit injects a
sequentially coded measuring signal into the monitored system. The
signal flows to ground via the path of the insulation fault, the level
of flow indicates the insulation resistance. The measuring accuracy is
not influenced by any normal kind of load attached to the AC network.
MEGGER SAFE
When auxiliary power is OFF the unit
input is automatically protected against "megger" test voltages up to
1.4kVDC, and incorrect measurements caused by the unit’s input
impedance are avoided.
OUTPUTS
The unit is supplied with an
isolated
analogue output proportional to insulation level. If output is
used for remote meter reading, we recommend 0-1mA for the slave
indicator.
SAFETY
The MCM161x range is designed to comply with specification IMCA D 045
"Code of Practice for the Safe Use of Electricity Under Water" issued by
IMCA.
The unit meets IEC60092-504 and the relevant environmental and EMC
tests specified in IEC60068/60092 and IEC61000/60533 respectively, to
comply with the requirements of the major Classification Societies.
The Ultra-Reliability Concept (Paralleling of Transducers)
To obtain ultimate operational safety multiple MCM161x transducer inputs and outputs can be permanently paralleled.
At any time only ONE transducer should be enabled. The selected
transducer is activated by applying auxiliary power to unit. Accidental
enabling of more than one transducer will give distorted reading, but
will not harm the transducer.
NOTE
Special versions of the MCM161x are available as:
MCM161xM
Insulation Transducer with DC detection function, protected against high-energy DC voltage imposed on the monitored AC supply.
MCM261x
Insulation Transducer with measuring loop continuity monitoring.
