Phase-Asymmetry Relay Type PS2DK
Phase-Asymmetry Relay for monitoring of Phase-Asymmetry and Phase Sequence
Phase asymmetry relays PS2DK are used for the protection of electric motors against asymmetries in the 3-phase mains without neutral and for monitoring the phase-sequence.
The switching-point is adjustable and can be adapted to the situation in the mains. If a motor, running with 2 phases, creates the 3rd phase, the sensitivity can be increased. With mains with high harmonics it can be necessary to reduce the sensitivity.
When the sensitivity is reduced to minimum (25% = potentiometer turned fully right) , the device works as a phase-sequence relay. It trips only at wrong phasesequence or missing phase.
If there is a wrong phase-sequence when switching on the device, the relay does not pick up.
- Monitoring of phase-asymmetry
- Monitoring of phase-sequence
- Adjustable sensitivity 5…25 %
- Output-relay with 2 change-over contacts
- Switching delay adjustable 0,1 … 5 s
- LED for display state of operation
Rated supply Voltage Us
3-phase 380-415 V, without neutral
app. 3 VA
2 change-over contacts
Type of contact
type 2 see General technical informations
rated ambient temperature range
Switching point asymmetry
Delay at phase-loss (< 240 V)
app. 0,2 s
Switch-back delay at voltage recovery
app. 0,5 s
Switching-delay at asymmetry
Switching point at symmetric decrease of voltage
Dimensions (H x W x D)
Housing K: 75 x 22,5 x 115 mm
on 35 mm DIN-rail or with screws M4 (option)
Protection housing / terminals