Low-Voltage Detectors

A low-voltage detector is a hand-held device that shows within seconds whether a conductor in a panel, feeder, socket or cable is live before work begins. All HASEGAWA models in this subcategory are pen-type, fit in a pocket and serve as the first check in day-to-day maintenance. Building and factory electricians, panel assembly teams and battery and UPS service technicians are the main users.

Two questions decide the choice: is the circuit to be checked AC only, or is there DC as well? And is the working environment a dark panel interior or a well-lit installation?

Which model?

Model	Operating voltage	Typical use
HTE-610W	AC 50 V – 1000 V	Building installations and industrial panels; detection through the cable sheath
HTE-610WL	AC 50 V – 1000 V	Dark panel interiors and ceiling voids; built-in LED torch
HTE-700D / 700DL	AC 50 V – 600 V; DC 12 V – 750 V	Battery banks, UPS, DC control circuits; IPX4-equivalent protection

The HTE-610W and HTE-610WL have identical measuring characteristics: both offer sensitivity adjustment and impulse withstand equivalent to IEC 61010-1 CAT III 1000 V. What sets the WL version apart is its LED light, which switches off automatically after about 30 seconds. On AC networks above 600 V, for example 690 V motor supplies, the AC upper limit of the HTE-700D/700DL is exceeded, so the 610 series should be chosen. On the DC side only the HTE-700D/700DL works; DC detection requires the earthing lead to be connected.

Points to note in use

• Before measuring, try the device on a point known to be live, and repeat the same check after measuring.
• Non-contact detection may not be possible on shielded (screened) cables and on lines inside metal conduit; the absence of a warning is not, on its own, proof that a circuit is dead.
• These models are not used on systems above 1000 V; at that level, move to medium / low-voltage detectors.

For other voltage classes see voltage detectors; for measuring methods see our article Contact vs Non-Contact Voltage Detectors.

Frequently Asked Questions

Which model is used on solar PV DC lines?

In this category the model that detects DC is the HTE-700D/700DL, with a DC upper limit of 750 V. It must not be used on systems whose string voltage exceeds this value; send us your system voltage and we will assess suitability with you.

Which model should be standard for a team?

If the team works only on AC installations, the HTE-610W, or the HTE-610WL for dark areas, is sufficient. If the team also works on DC circuits, the HTE-700D/700DL should be added to the team kit.