Dielectric Strength; Control Power - GE L30 Instruction Manual

CHAPTER 3: INSTALLATION

3.3.2 Dielectric strength

Dielectric strength is the maximum electric strength that can be sustained without breakdown. It is measured in volts.
The table shows the dielectric strength of the UR-series module hardware.
Table 3-1: Dielectric strength of UR series modules
Module type Module function
1 Power supply
1 Power supply
1 Power supply
2 Reserved
3 Reserved
4 Digital contact inputs/
outputs
5 Analog inputs/outputs
6 Digital contact inputs/
outputs
7 G.703
RS422
8 CT/VT
9 CPU
Filter networks and transient protection clamps are used in the hardware to prevent damage caused
by high peak voltage transients, radio frequency interference (RFI), and electromagnetic interference
(EMI). These protective components can be damaged by application of the ANSI/IEEE C37.90
specified test voltage for a period longer than the specified minute.

3.3.3 Control power

Control power supplied to the relay must be connected to the matching power supply range of the
relay. If voltage is applied to the wrong terminals, damage can occur.
The L30, like almost all electronic relays, contains electrolytic capacitors. These capacitors are well-
known to deteriorate over time if voltage is not applied periodically. Deterioration can be avoided by
powering up the relay at least once a year.
The power supply module can be ordered for two possible voltage ranges, and the L30 can be ordered with or without a
redundant power supply module option. Each range has a dedicated input connection for proper operation. The ranges
are as follows (see the Specifications section of chapter 2 for details):
• Low (LO) range — 24 to 48 V (DC only) nominal
• High (HI) range — 125 to 250 V nominal
The power supply module provides power to the relay and supplies power for dry contact input connections.
The power supply module provides 48 V DC power for dry contact input connections and a critical failure relay (see the
Typical Wiring Diagram earlier). The critical failure relay is a form-C device that is energized once control power is applied
and the relay has successfully booted up with no critical self-test failures. If on-going self-test diagnostic checks detect a
critical failure (see the Self-Test Errors section in chapter 7) or control power is lost, the relay de-energizes.
For high-reliability systems, the L30 has a redundant option in which two L30 power supplies are placed in parallel on the
bus. If one of the power supplies becomes faulted, the second power supply assumes the full load of the relay without any
interruptions. Each power supply has a green LED on the front of the module to indicate that it is functional. The critical fail
relay of the module also indicates a faulted power supply.
L30 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
Terminals
From To
High (+); Low (+); (–) Chassis
48 V DC (+) and (–) Chassis
Relay terminals Chassis
N/A N/A
N/A N/A
All Chassis
All except 8b Chassis
All Chassis
All except 2b, 3a, 7b, 8a Chassis
All except 6a, 7b, 8a Chassis
All Chassis
All Chassis
WIRING
Dielectric strength
2000 V AC for 1 minute
2000 V AC for 1 minute
2000 V AC for 1 minute
N/A
N/A
2000 V AC for 1 minute
< 50 V DC
2000 V AC for 1 minute
2000 V AC for 1 minute
< 50 V DC
2000 V AC for 1 minute
2000 V AC for 1 minute
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