hager hw+ User Manual

64 6LE008146B
Advanced protection functions
5.2 Undervoltage protection (UV-27)
The undervoltage protection (UV-27), ANSI 27 permanently monitors the installation voltage.
When the voltage exceeds acceptable limits, either the circuit breaker trips and a trip alarm is
generated, or only an advanced protection alarm is generated.
In addition, continuous monitoring of phase-phase or phase-neutral voltages allows the
appropriate action to be performed to secure the electrical installation such as load-shedding,
switch of power source, start of a backup generator.
Operating principle
These undervoltage protections allow the three phase-phase voltages to be monitored or the
three phase-neutral voltages.
It launches at the end of the activation time delay when one of the three voltages reaches the
activation threshold.
V0
t (s)
Vmin
tVmin
Adjustment parameters
UV-27
ANSI 27
Config.
Configuration of the protection
Inhibit Inhibition of the protection
Type U/ V
Choice U: L-L = phase-phase voltage, V: L-N = phase-neutral voltage
Threshold Activation threshold Vmin
Time Activation time delay tVmin
Configuration
The Configuration parameter defines the protection behaviour when the activation threshold
and the time delay are reached.
Trip Circuit breaker tripping
Alarm Alarm without tripping the circuit breaker
O Protection deactivated (default setting)
Inhibition
The protection is only deactivated if its inhibition parameter is set to On.
This parameter allows the protection action to be inhibited temporarily based on a command
sent in one of the following ways:
- sentinel Energy display from the MODE menu
- Hager Power setup software (Commands menu)
- Digital input (DI): assignment of the digital input to the inhibition required
- Modbus communication.
On The protection is inhibited while the inhibition command is at On
O The protection is fully operational while the inhibition command is at O
Vmin: activation threshold of the undervoltage
protection
tVmin: activation time delay of the
undervoltage protection

hager hw+ Specifications

General

Brand	hager
Model	hw+
Category	Circuit breakers
Language	English