Universal-Joint High-Voltage Detectors

Universal-joint high-voltage detectors are not supplied with their own stick; they are fitted via a universal joint to the end of the universal operating (switching) stick already used on site. Substation operators and switchyard maintenance teams that already have a fleet of insulating sticks procure only the detector head instead of a separate hot-stick detector. The suitability of the stick for the voltage class and reach concerned must be checked separately.

The category contains 10 models from AC 1 kV to 550 kV. The HWB and HST-V series offer parallel options at the same voltage levels; the HWA series focuses on medium voltage.

Which model?

Model	Operating voltage	Typical use
HWA-33P	AC 1 kV – 35 kV	4-step voltage indicator; MV cubicles and lines
HWA-33X	AC 11 kV – 33 kV	IEC 61243-1 compliant; hook, straight and Y-type tips
HWB-35	AC 6 kV – 35 kV	Medium-voltage distribution installations
HST-35V	AC 6 kV – 35 kV	Medium-voltage distribution installations
HWB-110	AC 35 kV – 110 kV	66 kV-class installations
HWB-138	AC 66 kV – 138 kV	High-voltage switchyards
HST-138V	AC 66 kV – 138 kV	High-voltage switchyards
HWB-550	AC 210 kV – 550 kV	380 kV / 400 kV transmission installations
HST-550V	AC 210 kV – 550 kV	380 kV / 400 kV transmission installations
HWB-550A	AC 11 kV – 550 kV	Wide range with a single head

The HWA-33X signals the approach to the target voltage with a 3-step visual and audible warning; its interchangeable tip makes it easier to work on different busbar and conductor types. You can compare the design differences between the HWB and HST-V series on the product pages or ask us.

Points to note in use

• After fitting the head to the stick, check that the joint is firmly seated and that the measuring angle allows the conductor to be reached.
• Before measuring, check the detector with a voltage detector tester.
• The voltage class of the stick used must meet the upper value of the detector's operating range.

For other detector types see voltage detectors; for maintenance and inspection intervals see our article Periodic Inspection of Voltage Detectors.

Frequently Asked Questions

Which universal-joint detector is suitable for 150 kV-class systems?

The HWB-138 and HST-138V end at 138 kV, while the HWB-550 and HST-550V start at 210 kV. The universal-joint model covering 150 kV-class systems (e.g. 150 kV or 154 kV) is therefore the HWB-550A, with a range of AC 11 kV – 550 kV. If a model supplied with its own stick is preferred, the hot-stick HST-170 can also be considered.