HST-30L Hot Stick High Voltage Detector

HASEGAWA HST-30L is a hot stick medium voltage detector built for the AC 3 kV – 34.5 kV medium-voltage range. It is the lowest voltage class in the L series and has the lowest threshold voltage in the series (500 V ± 100 V). Manufactured in Japan by Hasegawa Electric, the HST-30L is supplied as a genuine HASEGAWA product by HASEGAWA Türkiye, the official distributor in Türkiye.

DSO field crews, factories operating MV customer substations, industrial estates and electrical contractors use it for the voltage check carried out after disconnection and immediately before earthing. Common network levels such as 6 kV, 10 kV, 15 kV, 20 kV and 30 kV are all within its scope.

Where is it used?

• Pole-mounted transformers: Voltage checks on MV incoming conductors before maintenance or fuse replacement.
• Modular switchgear and compact substations: Verification at cable terminations and busbar connections before the earthing switch is closed.
• Industrial ring networks: Confirming that the section opened in a ring network really is dead.
• Contracting and acceptance work: Status checks on newly built MV lines before and after energisation.

HST-30L or HST-70L?

	HST-30L	HST-70L
Operating voltage (AC)	3 kV – 34.5 kV	20 kV – 80.5 kV
Threshold voltage	500 V ± 100 V	3000 V ± 600 V
Dielectric strength test points	1	3
Operating temperature	−10 °C … +50 °C	−10 °C … +50 °C
Weight	Approx. 3 kg	Approx. 3 kg

The deciding factor is the highest voltage level you work on: on networks not exceeding 34.5 kV the HST-30L is sufficient; if you also enter 66 kV installations, the HST-70L is required. The HST-30L's low threshold helps it respond at levels at the lower end of the range, such as 6 kV. If you are looking for a model in the same voltage range that is offered in long-stick versions, see the HST-30 page.

Technical specifications

• Operating voltage: AC 3 kV – 34.5 kV, 50/60 Hz
• Threshold voltage: 500 V ± 100 V
• Dielectric strength: AC 75 kV per 300 mm on the stick, 1 minute, at 1 point
• Leakage current: 0.1 mA or less in the withstand test
• Battery: 2 × LR44 (1.5 V); approx. 4 hours continuous operation
• Operating temperature: −10 °C … +50 °C
• Weight: approx. 3 kg

Limits of use and safety

The HST-30L must not be used on lines above 34.5 kV. Because of its 3 kV lower limit, it does not give reliable results on low-voltage boards either; low voltage detectors should be chosen for this work. Because the threshold is low, induced voltage on a circuit running next to a live line can trigger an indication; in that case, confirm on the network side that the line really has been isolated. Before every use, test the detector with a voltage detector tester, and do not proceed with the measurement if the battery is weak. The user must wear gloves suitable for the MV class, hold the stick only by the grip area and not work outside the −10 °C … +50 °C range. A "no voltage" result is not sufficient to start work without earthing.

Why buy from HASEGAWA Türkiye?

• We help you decide between the HST-30L and HST-30 for your lines from 6 kV to 34.5 kV
• We can add spare LR44 batteries and suitable voltage detector testers to the same order
• Same-day quotation on business days, with a commercial invoice, for industrial estates and plants