Sentinel™ TS-EFI-10 User’s Manual
Version 3.0 Page 5 of 9
2. OPERATION
2.1 CHARGING
Plug the external battery charger cable jack into the charging socket located on the side of the Test
Set. Allow up to several hours for the internal battery of the Tester to be charged. The charger will
usually have a red LED to indicate charging and a green LED to indicate when unit is fully charged. A
fully charged Tester will usually be able to test at least 100 EFI’s before requiring to be recharged.
2.2 CURRENT INJECTION
This Tester has been designed to test the basic trip functionality of EFI's. It has not been designed
to inject highly accurate current waveforms. The Tester current output consists of a square wave
with a nominal RMS current of 10A. The actual RMS current has been designed to be about 20%
higher to allow for EFI accuracy tolerances and injection cable contact resistance tolerances. The
output waveform is a square wave with a duration of 10 cycles (200ms at 50Hz).
The Tester output injection lead consists of a flexible cable. When testing an EFI, the cable is passed
around the core of the EFI current transformer several times and then plugged into the socket on
the Tester. The nominal injection current seen by the EFI is equal to the number of injection lead
turns around the current transformer multiplied by the nominal injection current. So for example,
an injection current of 50A can be generated by passing the injection lead 5 times around the EFI
current transformer (50A=5x10A).
Initiation of a test current is performed by depressing the “INJECT” pushbutton for at least half a
second. The output current injection is accompanied by illumination of the green LED labeled
“CURRENT OUTPUT””, as well as by a warble tone emitted from the audio buzzer. The red alarm LED
labeled “OPEN CIRCUIT” illuminates during the current injection if the output current lead is not
firmly fastened closed or if the contact resistance between the plug and socket is too high. The red
alarm LED labeled “LOW BATTERY” illuminates during the current injection if the internal SLA battery
needs to be recharged. Both alarms are also accompanied several warning beeps from the audio
buzzer. If the red alarm LED's do come on they will extinguish after a successful current injection or
after about 2s of inactivity.
The Tester output voltage is completely harmless being equal to or less than 12 volts under all
conditions. The Tester design inherently prevents any shock potential from developing across its
output under any electronic or mechanical failure mode. However the user should be aware that
during live conditions on site the equipment under test is connected to the electricity grid and has
the potential to have extremely hazardous and lethal high voltages. The user should take the
necessary safety precautions as discussed later in this document under the section titled “SAFETY”.
