Ultimate Power www.upinverters.com
Charging depleted batteries
The SD Series inverter allows start up and through power with depleted batteries.
For 12VDC model, after the battery voltage goes below 10V, if the switch is still(and always) kept in
"ON" position, the inverter is always connected with battery, and the battery voltage doesn’t drop
below 2V, the inverter will be able to charge the battery once qualified AC inputs.
Before the battery voltage going below 9VDC, the charging can activated when the switch is turned
to “Off”, then to “ON”.
When the voltage goes below 9VDC, and you accidently turn the switch to OFF or disconnect the
inverter from battery, the inverter will not be able to charge the
battery once again, because the CPU lose memory during this
process.
Start up without battery function can be customized upon request.
The charging capacity will go to peak in around 3 seconds; this may
probably cause a generator to drop frequency, making inverter transfer to battery mode.
It is suggested to gradually put charging load on the generator by switching the charging switch from
min to max, together with the 15s switch delay, our inverter gives the generator enough time to spin
up.
3.3 AC Transfer
While in the Standby Mode, the AC input is continually monitored. Whenever AC power falls below
the VAC Trip voltage (90 VAC, default setting), the inverter automatically transfers back to the
Invert Mode with minimum interruption to your appliances - as long as the inverter is turned on. The
transfer from Standby mode to Inverter mode occurs in approximately 10 milliseconds. And it is the
same time from Inverter mode to Standby mode.
Though it is not designed as a computer UPS system, this transfer time is usually fast enough to hold
them up.
There is a 15-second delay from the time the inverter senses that continuously qualified AC is
present at the input terminals to when the transfer is made. This delay is built in to provide time for a
generator to spin-up to a stable voltage and avoid relay chattering. The inverter will not transfer to
generator until it has locked onto the generator’s output. This delay is also designed to avoid frequent
switch when input utility is unstable.
3.4 Auto Frequency Adjust
The inverter is designed with Auto Frequency adjust function.
The factory default configuration is 60Hz for the SD series inverter
While the output freq can be easily changed once a qualified freq is applied to the inverter.
If you want to get 60Hz from a 50Hz inverter, just input 60Hz power, and the inverter will
automatically adjust the output freq to 60Hz and vice versa.
NOTE: The inverter will output factory set freq after it restarts.
