GE Multilin 745 User Manual

Typical Wiring745
Transformer Management Relay
Installation
http://www.GEindustrial.com/multilin
3–10
GE Multilin
FIGURE 3–12: Zero-Sequence (Core Balance) CT Installation
AC Voltage Input The 745 has one voltage divider type input for AC voltages. There are no internal
fuses or ground connections. Voltage transformers up to a maximum 5000:1 ratio
may be used. The nominal secondary voltage must be in the 60 to 120 V range.
Logic Inputs External contacts can be connected to the 16 logic inputs. As shown, these contacts
can be either dry or wet. It is also possible to use a combination of both contact
types.
A dry contact has one side connected to Terminal D11. This is the +32 V DC voltage
rail. The other side is connected to the required logic input terminal. When a dry
contact closes, a 2.2 mA current flows through the associated circuit.
A wet contact has one side connected to the positive terminal of an external DC
power supply. The other side is connected to the required logic input terminal. In
addition, the negative side of the external source must be connected to the relay DC
NEGATIVE rail at terminal D12. The maximum external source voltage for this
arrangement is 300 V DC.
Correct polarity must be observed for all logic input connections or
equipment damage may result.
FIGURE 3–13: Dry and Wet Contact Connections
CAUTION
Dry Contact Connection
Wet Contact Connection
745 RELAY745 RELAY
D11
D1D1
D11
+32VDC
+32VDC
Logic Input 1
Logic Input 1
32VDC
32VDC
DC Negative
DC Negative D12
D12
30 to 300 V DC
LOGICIN.CD
R

GE Multilin 745 Specifications

General

Brand	GE
Model	Multilin 745
Category	Relays
Language	English