HRB1684301-16

Direct connect voltage limits

You can connect the meter’s voltage inputs directly to the phase voltage lines of the power system if the power system’s line-to-line or line-to-neutral voltages do not exceed the meter’s direct connect maximum voltage limits.

The meter's voltage measurement inputs are rated by the manufacturer for up to 400 V L-N / 690 V L-L. However, the maximum voltage allowed for direct connection may be lower, depending on the local electrical codes and regulations. In US and Canada the maximum voltage on the meter voltage measurement inputs may not exceed 347 V L-N / 600 V L-L.

If your system voltage is greater than the specified direct connect maximum voltage, you must use VTs (voltage transformers) to step down the voltages.

Power system description Meter setting Symbol Direct connect maximum (UL) Direct connect maximum (IEC) # of VTs (if required)
Single-phase 2-wire line-to-neutral 1PH2W LN 347 V L-N 400 V L-N 1 VT
Single-phase 2-wire line-to-line 1PH2W LL 600 V L-L 690 V L-L 1 VT
Single-phase 3-wire line-to-line with neutral 1PH3W LL with N 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 2 VT
3-phase 3-wire Delta ungrounded 3PH3W Dlt Ungnd 600 V L-L 600 V L-L 2 VT
3-phase 3-wire Delta corner grounded 3PH3W Dlt Crnr Gnd 600 V L-L 600 V L-L 2 VT
3-phase 3-wire Wye ungrounded 3PH3W Wye Ungnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 2 VT
3-phase 3-wire Wye grounded 3PH3W Wye Gnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 2 VT
3-phase 3-wire Wye resistance-grounded 3PH3W Wye Res Gnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 2 VT
3-phase 4-wire open Delta center-tapped 3PH4W Opn Dlt Ctr Tp 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 3 VT
3-phase 4-wire Delta center-tapped 3PH4W Dlt Ctr Tp 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 3 VT
3-phase 4-wire ungrounded Wye 3PH4W Wye Ungnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 3 VT or 2 VT
3-phase 4-wire grounded Wye 3PH4W Wye Gnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 3 VT or 2 VT
3-phase 4-wire resistance-grounded Wye 3PH4W Wye Res Gnd 347 V L-N / 600 V L-L 400 V L-N / 690 V L-L 3 VT or 2 VT
NOTE:
  • Use a 500 mA fuse or a circuit breaker for the meter voltage input terminals.

  • Use a shorting block between the current transformer (CT) and the meter current input terminals.

  • Use primary fuses and disconnect switch to protect the potential transformer (PT).

QR Code is a registered trademark of DENSO WAVE INCORPORATED in Japan and other countries.

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