The R731 optional three phase sensing modul is designed to be used with the R438, R448, R449 single phase sensing voltage regulators.The voltage sensing is done with three 2VA single phase transformers.The R731 module is designed to be installed vertically next to the voltage regulator.
2 typical wiring schematics are provided :
- with the CT for parallel operation on the phase U
- with the CT for parallel operation on the phase V
Input voltage :
- High voltage tap (400V) : 340V-5% to 480V=5%
- Medium voltage tap (230V) : 200V-5% to 240V+5%
- Low voltage tap (110V) : 90V-5% to 140V+5%
Internal voltage rheostat :
The voltage can be adjusted using the internal rheostat P1. This rheostat is designed to provide +/-5% adjustment from any voltage within the above voltage ranges.
Remote voltage rheostat :
If required, remove the ST10 jumper in order to connect a remote voltage rheostat.
A 470 Ohms - 3W rheostat can be used for a +/-5% voltage adjustment range or a 1k Ohms - 3W rheostat for a +/-10% voltage range.
An ST1 jumper was included on older R731 modules to increase the voltage adjustment range but was discontinued.
Current sensing : C.T. for // operation
Location : standard line 1 (U), option line 2 (V).
- Maximum continuous current : 1.3A
- Nominal current : 1A
- Maximum current for 10s : 10A
Voltage droop rheostat :
The P2 rheostat on the R731 can be used to adjust the voltage droop. It is designed to provide a minimum voltage droop of 8% at 0 power factor and 1A from the paralleling CT.