I bought split A.C 1.5 ton Samsung AR18FC5efbh model. Can I use an 800VA Microtek UPS as stabilizer for this 1.5 ton A.C?

AC Specs http://shopping.indiatimes.com/electronics/split-ac/samsung-1-5-tonsplit-ac-ar18fc5efbh/10291/p_B1619918

Model: 800 VA Microtek ups with below specs:

Technical Specifications

Model MDP800

Input Range 135~300V AC

Frequency (50Hz+5%)

Output Voltage 230V ± 9% AC

Transfer Time <6ms

Regulator on Mains Automatic Voltage Regulation

Regulator on Battery Pulse Width Modulation

Unit Input Protection Fuse Protection

Noise Protection Noise Filter

Short Circuit (Line) Fuse Protection

Short Circuit (Inverter) Pulse to Pulse Electronic active Protection

Battery Type SMF

Recharge Time 2~8 Hrs. (depending on the status of Battery)

Backup Time 25-50 Min.

Batery Rating (Load 1PC) / 12V, 7.2AH x 2

Alarm Battery Backup (Sound beeping) Per 20 sec. (Approx.) Battery Low Sound beeping long

LED Display Green Mains mode operation / AVR Working

LED Display Red Inverter output from battery

Physical Size (L x W x H) (300x125x170)mm

Weight (Approx.): 11Kg.


Operating Temperature 0ºC ~ 48ºC ; 32ºF ~ 120ºF

Rel. Humidity 0 to 90% non-condensing

Noise Audible Noise level <35dB, distance 1 meter from UPS

  • Aside from the horrible formatting, you haven't provided any electrical specs for the AC unit you are trying to protect. That type of UPS is for a small computer not an A/C, so I'm tempted to answer no.
    – Steven
    Oct 8, 2013 at 13:11
  • Provided an edit with links to technical specs. The larger question, and my assumption is, that surendar is questioning whether the inside portion of this split AC unit can be connected to a consumer-grade UPS.
    – Jacob S
    Oct 8, 2013 at 13:24
  • Why do you think you need a power conditioner for your A/C?
    – mac
    Oct 8, 2013 at 16:35

2 Answers 2


The key facts about your A/C are

Power Requirements  1/230V/50Hz
Cooling Operating Current   7 A

7 A x 230 V = 1610 Watts. UPS specs are in VA not W due to power-factor corrections which I'll ignore:

Your 800 VA UPS is probably not a good choice for a 1610 W load.

  • Just a note -- simply looking at the wattage wont tell you the whole story. An 800W (per hour) supply (800VA = 800W) can, in theory, power at 1600W (per hour) device for 30 minutes. The problem has to do with current draw more than available power.
    – Jacob S
    Oct 8, 2013 at 13:47
  • @Jacob: 800 watts = 800 joules of energy per second. A device that needs 1600 joules of energy per second won't do its job properly if it is only supplied with 800 joules each second. You could do the calculation in terms of current draw at 230 V but it's convenient to use power. Oct 8, 2013 at 14:34
  • 1
    @JacobS: That's incorrect. Watts are not a measure of energy, they're a measure of energy-per-time (this is why your monthly electric bill is in kilowatt-hours). You should not use a UPS that is not designed to output that much power: if it's a good UPS, it will probably shut itself off. A bad UPS will probably break, and could easily overheat and catch fire. There's more to batteries than just how much energy they store. Oct 8, 2013 at 15:04
  • Definitely my confusion on that. -- Like I said, I can always be wrong. Thanks for the correction. But I agree with your sentiment.
    – Jacob S
    Oct 8, 2013 at 15:14

The interior unit is rated at 7A (1,570W) on 230V AC, power ratings for AC units are rated for "operating" power usage, not startup.

In addition, your 800VA UPS is rated in running time but does not list max current draw. You have to realize that the batteries are two 12v 7Ah batteries. While this might theoretically provide the A/C line stabilization that you are concerned about, without a max current draw rating or sustained operating information (V, W), it is entirely unknown as to whether this could possibly catch fire or if the batteries could, in theory, explode, especially while operating at the time of a complete power loss. While it is not entirely likely, it is also not impossible.

If you are concerned that you are in an area with unstable power/frequent spikes and brown-outs, you should consider a properly rated "Line Conditioner" rather than a battery backup that is intended for use with computer.

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