The 750ADM-H mk2 are compact, rugged primary current injection systems with a 750A output capability. The 750ADM-H has a maximum voltage of 5V. The unit is ideally suited to all low power primary injection tasks requiring up to 750A for short periods.

Where higher currents and powers are required for primary injection, 7kVA and 20kVA primary injection systems are available. The PCU1-SP and PCU2/E systems have separate control and loading units, allowing a wide range of load conditions to be covered with different loading units.

The 750ADM-H has two outputs, allowing injection of currents as low as a few hundred milliamps and up to 750A. Voltages up to 16V are available on the 40A output, allowing higher impedance trips to be tested. Four true RMS metering ranges are provided, allowing the full scale of the meter and trip level to be set independently of the selected output. The metering has a capture time of less than 20ms, allowing the RMS of a single cycle to be accurately measured. Industry standard connectors are used on all inputs and outputs for convenience, reliability and safety.

The 750ADM-H is comprehensively protected by electronic overcurrent and thermal trips.

The timing system is very flexible without compromising ease of use, allowing trip times, reset times and reclose times to be quickly measured to a high degree of accuracy. Two contact inputs are provided, each of which may be trigged by a volt-free contact or a dc voltage. The contact inputs auto-sense for normally open or normally closed contacts.

The 750ADM-H can be used to test many devices including:

• Circuit breakers
• Primary injection of over-current relays
• Auto-reclosers
• MCB’s
• CT ratio (with external meter for secondary current)