500A - 25000A Primary Current Injection Tester Secondary Injection Test Set

What is it?

The SLQ Series Primary Current Injection Tester is a portable high‑current generator. It draws power from AC220V or AC400V mains and outputs 500A to 25,000A of true power‑frequency current, injected directly into the primary circuit of power equipment (circuit breakers, current transformers, busbars, etc.) to simulate rated load or fault current.

Purpose: Conventional secondary injection tests only check the relay logic, not the complete physical chain (CT → wiring → relay → breaker mechanism). The SLQ uses real primary‑side current to verify CT ratio, secondary loop integrity, protection settings, and breaker trip time – uncovering hidden issues such as CT saturation, hot terminals, or mechanical sticking that secondary tests miss.

Product Highlights

1. Primary injection, full‑chain verification – no blind spots
   Injecting current directly on the primary side recreates the real fault path. Whether it’s a wrong CT ratio, poor contact in the secondary loop, or an aging trip mechanism, a primary test will reveal it. Much more direct and reliable than secondary injection.

2. Wide range, one tester for multiple voltage levels
   Output from 500A to 25kA; power supply options AC220V or AC400V. Suitable from low‑voltage distribution rooms to 110kV substations. See Table 1 in the manual – e.g., SLQ-5/1000 (1kA), SLQ-12/4000 (2/4kA dual range), SLQ-150/25kA (25kA).

3. Customizable high‑accuracy timer – catch every deviation
   Optional 4/5/6‑digit timers with accuracy up to 0.1%RDG+1D, ranges from 0~99.99s to 0~999999s. Measures both millisecond protection trip times and hundreds of seconds of temperature rise tests.

4. Strict safety & duty cycle protection

   • 100% rated current: max 30s continuous

   • 85% output: max 90s

   • 75% output: max 180s
     Exceeding limits triggers a cooldown recommendation. Also requires reliable grounding before use and prohibits touching hot terminals.

5. Clear standard configuration – no hidden costs
   Includes control unit, booster (for separated models), user manual, certificate, factory report. High‑current test cables are NOT included – quote separately to avoid misunderstanding.

 System Diagram

Technique Index

1 Power supply: AC220V or AC 400V, 45Hz~65Hz.  The power supply voltage is depends on the power output capacity. Detail information is as table 1.

2 Maximum output current: 500A~25000A. Detail information is as table 1.

3 Impendence voltage: 8%

4 Idle current: 6%

5 Current distortion <5%

6 Current is measured from the secondary of current transformer which is installed in the internal of the current booster. The display mode is customized according to the requirement of customer from the follow list:

1> Analog Current Meter, accuracy class 0.5

2> 4 and 1/2 digitals current meter, accuracy class 0.5

7 work temperature:0~40 C, Humidity <90%

Table 1 Detail configurations for different model current injection tester

Typical Applications

• Primary injection trip test for overcurrent relays in substations

• On‑site CT ratio error & phase displacement calibration

• Breaker temperature rise & stability test at rated current

• AC high‑current source for busbar/cable thermal testing

Who should buy it?

• Power engineering companies, high‑voltage labs

• Power plant & substation maintenance teams

• Switchgear and CT manufacturers’ factory test departments

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