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Emax DC
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Model
Scale
Page No.
Doc. No.
Apparatus
1SDH000635R0002
L3728
14 Modules
14.1 PR120/V-PR120/LV MEASURING Module
14.1.1 General characteristics
The MEASURING module records and processes the voltages. The measurements are sent by the module to the protection release, enabling
the implementation of a set of protection and measurement functions. The module comes with a "Power" LED and a sealable isolator for dielectric
stiffness tests. The module also enables the relay to be powered.
The PR120/V-PR120/LV is used for voltages from 100V to 1000V, the PR120/
LV is used for voltages from 24V to 48V.
14.1.2 Front view
- "Power Line" LED (lit when busbar voltage
is On, see 14.1.3)
- Isolator
Before performing the dielectric stiffness test it is essential to turn the isolator into the Test position mode by turning
the screw anticlockwise until you reach the end of stroke position.
After performing a dielectric stiffness test, restore the isolator to its original position by turning it clockwise until you reach
the opposite end of stroke, because all the voltage protections are disabled while the isolator is in the test position.
At the end of the procedure, make sure that the Power line LED is on.
14.1.3 Powering the PR122/DC and PR123/DC units via the PR120/V-PR120/LV module
The PR122/DC and PR123/DC units are powered by the MEASURING module via the busbar voltage.
The following tables show the voltage values at the MEASURING module's input for which the relays and modules are enabled:
PR122/DC and PR123/DC Relay + PR120/K Module
ENABLING
Enabling threshold (Voltage)
PR122-PR123/DC Relay
PR120/K
Relay display backlighting
PR120/V
PR120/LV
60V
18V
90V
24V
Isolator
N.B. The PR120/V-PR120/LV module does not need any connections to be made by the customer.