HST-250 Hot Stick High Voltage Detector

HASEGAWA HST-250 is a hot stick high voltage detector operating from AC 150 kV – 287.5 kV, with the longest stick (5055 mm) among the standard HST models. It covers 150 kV transmission installations as well as intermediate transmission levels such as 220 kV. Manufactured in Japan by Hasegawa Electric, it is supplied as a genuine HASEGAWA product by HASEGAWA Türkiye, the official distributor in Türkiye.

The long stick keeps the user outside the large approach distances required around high-voltage equipment, making measurement easier. The HST-250 is chosen mostly by transmission substation operations teams, transmission line maintenance contractors and energy-intensive plants that operate their own high-voltage switchyard.

Where is it used?

• 150 kV – 220 kV substations: Points that require remote access to the conductor in switchyards with high busbars and wide phase spacing.
• Line entry gantries: Checks after an outage at the gantries where a transmission line enters the switchyard and at line disconnector outputs.
• Energy-intensive industry: Verification before periodic maintenance at steel, cement and chemical plants with their own high-voltage connection.
• 220 kV networks: EPC and maintenance work on transmission systems operating at 220 kV.

HST-250 or HSR-500?

	HST-250	HSR-500
Operating voltage (AC)	150 kV – 287.5 kV	250 kV – 550 kV
Typical level	150 kV – 220 kV	380 kV – 400 kV
Overlap	250 kV – 287.5 kV	250 kV – 287.5 kV

The 380 kV and 400 kV transmission levels exceed the upper limit of the HST-250, so the HSR-500 must be chosen for these installations. For 150 kV, the HST-170, which starts at 60 kV and has a 3145 mm stick, can also be considered alongside the HST-250; the decision usually depends on the reach required.

Technical specifications

• Operating voltage: AC 150 kV – 287.5 kV
• Standard stick length: 5055 mm
• Versions using the same stick: HST-30J, HST-70J, HST-170J
• Country of origin: Japan

Limits of use and safety

The HST-250 is not suitable for installations below 150 kV; at 66 kV and 33 kV, the HST-70 or lower-class models must be used. Because the 5055 mm stick is long, you need to keep your balance during measurement, bring the tip towards the conductor in a controlled way and take extra care in windy weather. Before use, check that the detector works with a suitable voltage detector tester or a point known to be live. The person taking the measurement must wear personal protective equipment suited to the voltage class and must not hold the stick outside the grip area. After the absence of voltage has been verified, the line must be earthed with transmission line earthing sets. For model selection, see our voltage detector selection guide.

Why buy from HASEGAWA Türkiye?

• We clarify the boundary between the HST-250 and HSR-500 for each of your 150 kV – 400 kV installations
• We shorten the purchasing process by combining transmission line earthing sets and the detector in one quotation
• For existing HST-30, HST-70 or HST-170 users, we supply the J versions with the 5055 mm stick to order