Step-Down Transformer or Auto Voltage Regulator

[jacorb_88]

I have circular saw 110v which I bought from US. It says on the spec sheet it's 2.3 HP and 13 amp. 2.3 HP could just be its peak HP and used as marketing ploy. As I understand, Watts = 2.3 HP x 745. This makes it roughly 1700 Watts. On the other hand, Watts/KVA = 13 amp x 110v. This gives around 1400 Watts/KVA. Bring in the Power Factor of 60%, 1400 KVA would be around 850 Watts.

a.) Is my understanding above correct?
b.) If so, to use my circular saw, should I use a step-down transformer or AVR?
c.) From calculated Watts above, would I be safe with 1500 Watts, considering from 2.3 HP equates to 1700 Watts? Which one should be my reference, the 110v 13 Amperes or 2.3 HP?

Thanks.

[opzuk4x4]

I would suggest you get a 1,500 watts step down transformer.

[stealthy]

i agree with opzuk4x4 that you should use the step down transformer but perhaps it would be safer to use a transformer with a rating that is 1.5 to 2 times the power rating of your tool. this is to avoid heating up the transformer during long usage.

i think it would be safer also to use the HP calculation for wattage. manufacturers usually put a safety margin in the specs to cater for worst case scenario. in this case, i think they used a 20% margin for the input voltage (130V) to come up with the HP rating.

i hope this helps :)

[JayL]

I have a Craftsman 13A 110V circular saw. I am currently using a STAC 1500 Watts voltage stabilizer with no problems at all. The added fused protection of a voltage stabilizer is a plus. This saw was accidentally plugged in to the stabilizer's 220V output by my helper without damage to the saw. Accidents do happen.

[jacorb_88]

Just an update.

Called one hardware store in Raon (CJR) to ask for a price and stock. They quoted me 2,900 for 2000w. When I got there, lady at the back office told me it's out of stock (to think, I came all the way from Makati).

I had the chance to jump from one shop to another. Unfortunately, they all said the same thing, out of stock. Went to NBK which they quoted me 3,500. However, the guy advised me to consider non-China made transformer to give me better value. Although locally made transformers are more expensive, it would still be a better buy in the long run.

I settled for 4,000 2000w locally made. It's huge and heavier as compared to china-made 3,500 2000w. Plus still have more space for higher wattages tools.

I got the feeling that this unit will outlast me ;)

Thanks again.

[JayL]

Hmmm ... what brand is it? I'm also thinking to get one. Most of my woodworking tools are 110 V and I could not use them simultaneously because I have only one voltage stabilizer.

Any update on the heat build up when the stabilizer is put into extended usage?

[jacorb_88]

Sorry JayL, I just tried it twice for no longer than 10 minutes per outing.

This is just a step-down transformer. I believe stabilizer is different. There's no fuse and meter reading.

Brand is Vertan.