KPM 16xM0 pages

AC INSULATION GUARD WITH HIGH ENERGY DC PROTECTION

KPM16xM
• Direct connection up to 500V line voltage, up to 5kV with
HV adapter
• Monitoring during both live and standby conditions
• Protection against harmful DC voltage exposure
• ”Megger” - safe to 1.4kVDC when aux power is OFF
• Immune to earth capacitance and voltage surges
• For use in land, marine, offshore, sub-sea and ocean floor
Installations
• Analogue output proportional to meter reading (F-version)
Application

Specifications
KPM161M & KPM161MF - KPM161GM & KPM161GMF
Scale range:
0-1000kΩ - (>10MΩ)
Network line voltage:
0-500V (40/400Hz)
Adjustments
Trip level
Delay
WARNING:
0-1MΩ
0-30secs
ALARM:
0-1MΩ
0,1-3secs
KPM163M & KPM163MF - KPM163GM & KPM161GMF
Scale range:
0-10MΩ - (>100MΩ)
Network line voltage:
0-500V (40/400Hz)
up to 5kV with voltage adapter
Adjustments
Trip level
Delay
WARNING:
0-10MΩ
0-30secs
ALARM:
0-10MΩ
0,1-3secs
General
Auxiliary Supply:
100-120, 200-240, 380-415 or
440-460VAC, 40-70Hz (Fuse 0.5A)
Optional Voltage:
12-24VDC (Fuse 2A)
Contact rating:
AC: 100VA - 250V/2A max.
DC. 50W - 100V/1A max.
Analogue Output:
Up to 20mA, max 500R
Up to 10V, min 100kohm
(other on request)

Temperature:
Weight:
Front protection:

-20 to +70ºC
0.62kgs
IP54 (IP65 optional)

NOTE:
The standard Insulation Guards KPM161x and KPM163x are
protected against sporadic AC and DC voltage surges imposed
on the monitoredAC network.

The digitally controlled KPM16xM 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) in
marine and offshore installations.
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 to 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 theAC network.
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 KPM16xM can be connected to each IT-system. The ohmmeter and
the triple-zone status LEDs give at a glance the clear safety message:

- ALARM (red zone)
- WARNING (yellow zone)
- HEALTHY (green zone)

General
HIGH ENERGY DC VOLTAGE IN YOUR AC MAINS, AN UNKNOWNAND NEGLECTED PROBLEM
Experience has confirmed that full cycle half-wave and partial cycle full-wave rectifier/regulator loads, inverter
asymmetrical phases output or a semiconductor failure in heavy power rectifiers/inverters may impose high energy
DC voltage on the AC supply line voltages. Intermittent or ENDURING imposed DC voltage is reported to be up to
several hundred volts with positive or negative polarity relative to protective earth.
This DC voltage will distort insulation measurements, and may cause breakdown of protective guards The
uncontrolled DC energy can cause functional problems by saturating magnetic cores and influence performance of
current and voltage transformers, reactors, motors, regenerative drives, generators and regulators.
It is also a fact that this serious malfunction normally remains undetected and unknown to the crew. The M-variant
therefore includes a unique DC voltage detection function with an alarm output.

Exposure to enduring high energy DC voltage (reported to be up
to several hundred volts with positive or negative polarity) will
instantaneously cause the meter to read false insulation value
and may destroy the unit.

When a “foreign” positive DC voltage exceeding 17V or a negative DC voltage exceeding 3V are detected on the
monitored AC supply the DC detection function will within 20 seconds disable the insulation measuring function to
avoid false readings, isolate the unit input, activate LED “DC EXPOSURE” and trip relay 3. In this mode unit will
sustain continuos high-energy exposure up to +/- 800VDC. The “pathfinder” function identifies polarity of imposed
DC. At 10 minutes intervals the unit senses if DC is still present and will reset automatically and restore normal
operation when DC exposure ends.
To detect presence of harmful DC voltage connect a voltmeter between any AC supply line voltage and protective
earth, and set the meter function switch toAC and DC alternately.

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Norway - UK - Denmark

REF: Datasheet.KPM16xM - REV: 1.06
Megacon reserves the right to make any changes to the information at any time

www.megacon.com