ISUPS2B004 Rev 1
Page 19 of 70
Ampcontrol Pty Ltd
– ABN 28 000 915 542
ISUPS 300Wh V2 USER MANUAL
ISUPS2B004 R2
– DEC/17
5
OPERATION
The Intrinsically safe uninterruptible power supply exhibits very low output impedance. The output
voltage is reduced by an average of 0.4V at full load. Precise current limiting provides maximum
available current up to the Io parameter. The power supply output acts as a current limited voltage
source. The load impedance can vary down to short circuit while the maximum output current is
maintained. This is a safety feature; we recommend not exceeding the load that reduces the output
voltage to maintain the maximum output current.
The UPS has various configurable functions but for users who wish to use it in the simplest form an ex-
factory default setting is programmed into the unit prior to delivery. Refer to Section 10.5 & Section 10.7
for details on programming and customising as required to suit a specific application. A brief on the
functionality of the ex-factory default settings is given below:
The programmab
le output on time is set to “Always ON”, the output will remain on even when the
mains are switched off, and until the battery voltage reaches the low level. The output on time
can be programmed to any time at 10-minute steps. In this case, the output will stop when the on
time is expired. To initiate another cycle it is necessary to start the ISUPS either by using an
externally wired momentary switch, or the local keypad.
Application of mains power will override any timer function and will automatically switch the DC
output on if it is in an off status due to time out. If the UPS has been “stopped” by pressing the
local “STOP” button prior to loss of mains supply the output will not be energised by the return of
the mains supply.
The minimum battery voltage level will switch the output off automatically ignoring the timer
activity, as a self-protection feature.
Digital inputs are mapped 1 to 1 to the relays to mimic input status.
As part of its design as an Intrinsically Safe product the input AC supply to the UPS is protected by both
a ceramic fuse and resettable thermal fuse (NTC), which is encapsulated into the electronics assembly.
It is unlikely, but possible that repeated application of the mains supply over a short timescale (the
thermal fuse not having enough time to recover) could cause the ceramic fuse to blow if the AC power
supply is particularly noisy or at the limit of the permitted voltage.
To reduce any possibility of this protection device being activated it is recommended to avoid cycling
power to the UPS frequently. Please follow the time intervals shown below between the consecutive
applications of mains power to the UPS to avoid blowing the input ceramic fuse.
Table 2: Recommended Time Intervals between Power Cycling
Mains Input Voltage
Ambient Temperature
Power Up intervals
110Vac
≤40degC
30-seconds
110Vac
>40degC
60-seconds
240/250Vac
≤30degC
90-seconds
240/250Vac
>30degC
3-minutes
The Mains LED not illuminating when AC power is applied to the UPS would indicate activation of the
protective fuse. In this case, the UPS should be returned to Ampcontrol for service.
CAUTION!
Maintain the time intervals between successive applications of mains
power to the UPS. Multiple applications of mains power, at insufficient
intervals, may risk blowing the internal ceramic fuse. Replacing a blown
fuse will necessitate returning the unit to Ampcontrol for repairs (See
warning in Section 3, Product Overview). This repair could be time
consuming & expensive. (See detail above)
On receipt of your UPS, it should be in Stop mode. The front display will be off and the reset LED
flashing.
