NEGATIVE PHASE SEQUENCE
CURRENT ALARM RELAY

Types CIR210 & CIR210M

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The CIR210 is a sensitive frequency-compensated negative phase sequence (NPS) current relay providing measuring and alarm functions over the range 1 to 10% NPS of full load current for a frequency range of 47 to 51Hz. A calibrated meter which indicates the level of NPS current is situated on the front panel. The operating NPS level is set on a dial calibrated 0 - 10% and the output relay contacts operate after a delay time of between 6 and 105 seconds, presettable on a thumbwheel switch.

A 0-10mA dc current output corresponding to 0-10% NPS current is also included with an accuracy of ±0.5% NPS current as measured by the front panel meter and this will be maintained when driving a load of between 10 and 1000 ohms.

The level setting dial, the time delay control and the indicating meter are mounted on the relay front panel. The output contacts are self-resetting and a front panel lamp acts as a flag to indicate that the relay has operated. The lamp is reset manually using a push button mounted on the front panel.

The CIR210 is housed in a clear-fronted metal case which may be projection or flush mounted to suit and the CIR210M is housed in a size 6 modular case. Power requirements are 110Vdc at 50mA and the current inputs are 0-1A rms per phase.

Sets of interposing current transformers are available to enable the relay to be used with 5A secondary C.T. installations.

Complies with specification NGC-EM15. Instrument and Control NGC Approval No: 5120 A10 Issue 2.

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SPECIFICATION

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CURRENT INPUTS
Nominal Rating 1 amp rms
Maximum Continuous Current 1.5 x nominal
Short Time Rating 10 x nominal for 5 seconds
Frequency Range 47 to 51Hz
Input Burden 0.8VA per phase
POWER SUPPLY
Input Voltage  110V dc +25% -20%
Input Current 50mA maximum at nominal voltage
OPERATING VALUES
NPS Setting Range 1 to 10% of nominal current
 ±0.5% of nominal current
NPS Indication on Meter 0 to 10% of nominal
 ±0.5% of nominal
Time Delay 6 to 105 seconds
 ±1 second
Note The relay will function without maloperation
 over the range of zero to twice the maximum
 current rating and will correctly measure the
 NPS component over the range of input currents
 up to the maximum specified.
RESETTING DIFFERENTIAL The relay will reset at an NPS current
 of not less than 90% of its operating value.
RELAY OUTPUTS Two electrically separate, normally open, self-
 resetting output contacts are provided which are
 open when the relay is de-energised and closed
 when the NPS current exceeds the setting for the
  specified time. 
 One pair of normally closed output contacts held
 open when the PSU is healthy.

CONTACT RATINGS

	Make and Carry Continuously	Break
a.c. d.c.	1200VA with maximum of 5A and 240V 1200 Watts with maximum of 5A and 240V	1200VA with maximum of 5A and 240V 50 Watts resistive with maximum of 5A or 240V

NPS OUTPUT 0-10mA dc corresponding to 0-10% NPS current.
 Accuracy ±0.5% of nominal current when driving a
 10-1000 ohm load.
  Output is open-circuit and short-circuit proof.
INSULATION 2KV rms between all input circuits, output
 circuits and earth.
ELECTRICAL INTERFERENCE EES1980 Class Z.
ENCLOSURE
CIR210 The relay is housed within a die cast metal case
 finished in black semi-matt epoxy paint. A
 removable front cover containing a window
 allows access to the setting dials. All connections
 to the relay are made to an approved Klippon
  type MK 7/18 connector. Supplied complete with
 manual.
Dimensions: W : 174mm H : 203mm D : 163mm.
Weight: 3.7kg.
CIR210M The relay is housed in a yellow and black size 6 
 modular case. A removable clear front cover allows
 access to the setting controls. Supplied complete
 with manual.
Dimensions: W : 154mm H : 177mm D : 244mm.
Weight: 3kg. 

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Convex Design Limited

email:sales@convexdesign.co.uk

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