Voltage detector


with protective cover


The JSC-88A is a very reliable way to know for sure whether or not there is voltage downstream from the switches or breakers during power-ons. It dramatically increases the safety of personnel assigned to maintenance work on electrical equipment powered by threephase voltage. As long as voltage is present downstream of the breakers, one or more (LEDs) of the JSC-88A will stay on. The use of the optional KLQ-Kit enables an additional verification directly at the motor concerned. When one of the 3 LEDs lights up, the KLQ-Kit’s Remote LED will light up. A simple visual inspection tells you whether the electrical system is in “Zero Energy” mode.

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JSC-88A by Controlab INC

Technical sheet of Voltage Detector – JSC-88A

Small and designed to be mounted on its light socket, the JSC-88A can be easily installed on the door of the switchboard or starter. Our voltage detector, originally developed in 1988, is now widely used by many companies that care about the safety of their employees.

Important: If one or more LEDs remain lit, this indicates that the JSC-88A detects the presence of voltage and that the situation is definitely dangerous. A qualified electrician should then investigate the problem and take corrective measures.

There is no automatic correspondence between a given indicator and a particular phase. The JSC-88A were not designed to detect phase loss, but rather problematic voltage in industrial environments.

▶ High quality and small-sized design
▶ Two (2) year warranty
▶ CSA and UL approved
▶ Fully cast in epoxy
▶ NEMA-4X detector (standard)
▶ Human protection cover included
Works under three-phase
Operating voltages: 120 to 600 V
Operating frequency: 50/60/400 Hz
Current consumption: 1.9 mA
KLQ-Kit option: NEMA4X Remote Light
Designed to be connected to ground or neutral if allowed
Dimensions: 72 mm x 51 mm x 26 mm
Included: KIT-KA voltage step-down for installations up to 600V
On Request : Single-phase, bi-phase, DC ungrounded
1- Does the JSC-88A require a ground or neutral connection to function?

YES, otherwise neither of the 3 LED lights will turn on.

2- Is it still possible to connect a JSC-88A to a fully floating electrical system (Delta) without a ground?

YES, if you use our KD-Kit wiring kit, it will create an artificial neutral from the 3 phases that supply the voltage detector.  However, the presence of 2 or more phases is required so that this neutral can function properly and allow the JSC-88A LED lights to turn on.  If there is only one phase, there is no return path, therefore, none of the 3 LED lights will turn on.

3- Will the 3 LED lights on the JSC-88A turn on if the KA-Kit wiring kit is connected to resistors placed on the JSC-88A end instead of the switch end?

NO, because the KA wiring kit has a direction and the resistors must always be installed in the switch side.

4- Can the JSC-88A be used to detect a phase loss?

     NO, because its primary function is to detect the presence of voltage when a master switch is shut off.  When a phase loss occurs, regeneration produced by the other two phases onto the missing phase will allow the 3 LED lights to remain lit.

This is because there is also potential for reverse flow from the control transformer, the motor winding or even the electronic devices connected to said switch.  All these possibilities will allow the JSC-88A to detect voltage that could be dangerous for the electrician or maintenance engineer.  The JSC-88A is a device that was designed to save lives in an industrial environment by visually indicating the presence of a three-phase voltage.

5- Can I install a JSC-88A on any electrical system?

NO, because the JSC-88A requires a ground or neutral connection to light up.

6- When installing the KA-Kit voltage reducer kits with a JSC-88A, can the wires be installed in any direction?

NO, because the KA wiring kit has to be installed in the right direction for the JSC-88A LED lights to turn on correctly.  And, secondly, for security reasons mentioned in number 8.

Easy installation

The JSC-88A voltage sensor is fully calibrated in our laboratories and therefore delivered completely ready for operation. Installation takes about 10 minutes per device and can be carried out by anyone. Watch this video to learn how.

Need help? Contact our technical support

Need help? Contact our technical support

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Controlab products (phase imbalance detectors, voltage detectors, ground fault monitors) are sold through a network of distributors and OEMs covering all of North America. For questions or comments about Controlab products, please contact us.

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