GE MULTILIN 269 MOTOR MANAGEMENT RELAY Series Instruction Manual Download

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2 INSTALLATION

2-12

2.4 Control Power

The relay is powered on using any one of four
different switching power supplies: 120-125
VAC/VDC, 240-250 VAC/VDC, 48 VDC, or 24 VDC.
The first two versions have been designed to work
with either AC or DC control power. Maximum power
consumption for the unit is 20 VA.

The 269 will operate properly over a wide range of
supply voltages typically found in industrial
environments (see control power specifications in
section 1.5). When the supply voltage drops below
the minimum, the output relays will return to their
power down states but all setpoints and statistical
data will remain stored in the relay memory. Motor
lock-out time will be adhered to with or without control
power applied. If control power is removed, the relay
keeps track of the Motor Lockout time for up to an
hour.

Control power must be applied to the 269 relay, and
the relay programmed, before the motor is energized.
Power is applied at terminals 41, 42, and 43 which
are terminal blocks having #6 screws.

Note: Chassis ground terminal 42 must be
connected directly to the dedicated cubicle
ground bus to prevent transients from damaging
the 269 resulting from changes in ground
potential within the cubicle. Terminal 42 must be
grounded for both AC and DC units for this
reason.

Verify from the product identification label on the back
of the relay that the control voltage matches the
intended application. Connect the control voltage
input to a stable source of supply for reliable
operation. A 3.15A, slow blow mini fuse (see Fuse
Specifications in Technical Specifications) is
accessible from the back of the 269 by removing the
perforated cover. See Figure 2.8 for details on
replacing the fuse. Using #10 gauge wire or ground
braid, connect terminal 42 to a solid ground which is
typically the copper ground bus in the switchgear.
Extensive filtering and transient protection is built into
the 269 to ensure reliable operation under harsh
industrial operating environments. Transient energy
must be conducted back to the source through filter
ground. The filter ground is separated from the safety
ground terminal 42 at jumper J201 on the back of the
relay to allow dielectric testing of a switchgear with a
269 wired up. Jumper J201 must be removed during
dielectric testing. It must be put back in place once
the dielectric testing is done.

When properly installed, the 269 will meet the
interference immunity requirements of IEC 1000-4-
3/EN61000-4-3; EN 61000-4-6. It also meets the
emission requirements of IEC CISPR11/EN55011
and EN50082-2.

2.5 Phase CT Inputs

One CT for each of the three motor phases is
required to input a current into the relay proportional
to the motor phase current. The phase sequence
must be as shown in Figure 2.4 and Figure 2.7. The
CTs used can have either a 1 amp or 5 amp
secondary and should be chosen so that the motor
full load current is between 75 and 95 percent of the
rated CT primary amps. The CT ratio should thus be
of the form n:1 or n:5 where n is between 20 and
1500. The ratio of the CT used must be programmed
into the 269 (see section 3.7).

The CT connections to the relay are made between
the ":1" and "COM" terminals for 1 amp CTs or
between the ":5" and "COM" terminals for CTs with a
5 amp secondary.

The connections to the 269 internal phase CTs are
made directly via #10 screws.

CTs should be selected to be capable of supplying
the required current to the total secondary load which
includes the 269 relay burden of 0.1 VA at rated
secondary current and the connection wiring burden.
The CT must not saturate under maximum current
conditions which can be up to 8 times motor full load
during starting or up to 20 times during a short circuit.
Only CTs rated for protective relaying should be used
since metering CTs are usually not rated to provide
enough current during faults. Typical CT ratings are:

CSA (Canada):

Class10L100

10=accuracy,
L=protection,
100=capacity, higher is
better

ANSI (USA):

Class C 100 B4

C or T=protection,
100=capacity, higher is
better, B4=accuracy

IEC (Europe):

20 VA Class 5P20

P=protection,
20VA=capacity, higher is
better

Refer to Appendix H for details on CT withstand, CT
size and saturation, as well as the safe use of 600V
class window type CTs on a 5 kV circuit.