There are some questions that we are asked on a regular basis, and we will post answers to as many as possible here.


Q. What warranty do you offer on your products?

A. We offer a one year return to base parts and labour warranty as standard on all our products.

Current Injection

Q. I’m trying to inject a low current into a relay using your secondary injection set, but I can’t get fine enough control of the current. I’m using the 3A 240V output on the unit.

A. Although it may seem counter-intuitive, you should use the 10V 100A output on the unit, and set the metering range to 5A (or similar). Using the lowest output voltage range gives the best control. If you still can’t get fine enough control consider using the 100ADM-F filter unit or the RB-10 resistor box.

Q. Why am I unable to inject the current I require with my primary injection system?

A. Primary current injection systems have a very high current, low voltage ac output, and to get maximum output current it is necessary to minimise the impedance to the load. Firstly, tie the feed and return cables from the loading unit to the load together – this will minimise the loop inductance. The larger the area enclosed by the output loop, the higher the inductance and hence the lower the current will be. Using the shortest possible output cables will also help to maximise the output current.

High Voltage

Q. I’m checking the output voltage on my PT15-10, PT18-10 or PT30-10, and I’m only able to get to 30% of the rated output voltage.

A. Check that the output cables are connected. The output voltage is half-wave rectified, and needs the capacitance of the output leads to smooth the output voltage. The output voltage metering reads the average voltage, and without the smoothing of the output leads the average output voltage is very low.

Relay Testing

Q.How do I set a stability test using a DVS3 Mk2

A. Stability test using a DVS3 using the Pre-Fault, Fault, Post Fault.

Pre Fault: Nominal voltage. ( make sure there is enough time for the relay to stabilize.)

Fault: G59 voltage and test duration procedure recommended by the Energy Network Association.

Post Fault: returns to nominal voltage.

Please see below for description of the test setup that we had working.

Nominal Voltage (voltage where no trip condition) = 258.12V measured using a calibrated fluke, after the DVST-286 box.  DVS3 MK2 Screen voltage 117.0V.

Fault Voltage (Under voltage) = 188.16V. DVS3 MK2 screen voltage 85.3


Pre Fault:

Voltage: 258.12. (117.00)

Time Set: 20 seconds



Voltage: 188.16 (85.3)

Time Set: 2.45 seconds


Post Fault:

258.12. (117.00)

Time Set: 20 seconds.