Effective 11/2003
Page 9
I.L. 66A7535H02
There are four auxiliary current transformers with a ratio of
10:1 which further step down the rated current to 100 milli-
amperes, which is equivalent to 100% (
I
n) to the Digitrip.
The primary current sensors produce an output signal
proportional to the load current and furnish the Digitrip
1150V with the information and energy required to trip the
circuit breaker when functional protection settings are
exceeded.
If the CH Type-V current sensors and circuit breaker
enclosure label are changed to a different ratio, the rating
plug must also be changed. The associated rating plug
must match the current sensors installed and as specified
on the circuit breaker enclosure label. Refer to Figure 2.3
for CH Type-V current sensors available.
hole for the
View Functions
group of pushbuttons and the
Battery Test
push button.
1.6 Digitrip 1150V Power/Relay Module
The Power/Relay Module
(See Figure 1.7)
is a standard
device for the Digitrip 1150V model. The module is in-
stalled on the molded platform under the trip unit in the
circuit breaker. There are three style modules that cover
the following input voltage ratings: 120 VAC, 230 VAC, and
24-48 VDC. The burden of the Power/Relay Module is
10VA.
1.6.1 Auxiliary Power
When the module is wired and supplied with proper
voltage, it will provide an auxiliary power supply so that the
LED display will be functional even when the circuit
breaker has no load. A Digitrip 1150V unit
without
auxil-
iary power will not provide voltage protection (if selected),
display any data or provide communications.
1.6.2 Alarm Contacts
A second function of this module is to provide either a trip
or alarm output contact via the two customer programmed
relays within the module. An assortment of relay functions
can be assigned to these relays.
(See the Aux Relay
programming in Appendix D-15 and Appendix G).
Each
relay is a normally open contact with a programming
identification of RELAY A and RELAY C. On the Breaker
Master Connection Diagram (Appendix C) these contacts
are labeled ATR_Alarm and ATR_latch. The ATR_latch is a
latching relay that will hold contact status even if auxiliary
power is lost to the breaker. This relay does require
auxiliary power for resetting. The resetting of these relays
requires depressing the RESET pushbutton on the front
panel of the Digitrip 1150V.
1.6.2.1
Ground Alarm
A ground fault alarm is one of many possible program-
mable alarms and can provide an early warning of a ground
fault condition in progress via an alarm LED.
In addition, this unit can be programmed to energize an
alarm relay upon this condition. The alarm relay will reset
automatically if the ground current is less than the ground
alarm pickup setting.
1.6.2.2
Block Close Relay
Also in this module is a relay that can block the remote
closing of a circuit breaker after a trip condition. This Block
function is enabled by programming the Aux Relay B via
the front panel or via PowerNet communication
(See
Appendix D-15)
Figure 1.4 CH Type-V Current Sensor Installation
1.5 Plexiglass Cover
A clear, tamper-proof, plexiglass door sits on the breaker
cover. This door, if sealed, allows the settings to be viewed
but not changed, except by authorized personnel. It meets
applicable tamper-proof requirements and is held in place
by two screws. Security is insured by the insertion of a
standard meter seal through the holes in both of the cover
retention screws. This plexiglass cover has an access
