Help! converting to 220 on a hf dc

[Michael Reinhart]

Hi I am new here and would like to know if anyone would know if it is possible to convert a hf. 2hp 120 volt dust collector to 220 volt ? I tried contacting hf but they were no help.

[Van Huskey]

First look at the motor placard, does it show single or double voltage?

Second, why do you want to change it, do you only have a 240v outlet where you need it? If that isn't the reason I will just say you won't see any increased performance by going to 240V...

[Neil Brooks]

The conventional wisdom is ... no ... 110v only on the 2HP HF DC.

Sorry.

[Michael Reinhart]

I wanted to convert due to the large draw on start up and would also like to up size to 6" duct and was told this would create more draw on the motor. Thanks for the fast response

[Van Huskey]

I wanted to convert due to the large draw on start up and would also like to up size to 6" duct and was told this would create more draw on the motor. Thanks for the fast response

The inrush spike is VERY short, you will need something like a Fluke 330 or a recorder to even properly capture the 75-100ms spike. This usually doesn't cause any breaker trips but I agree it could cause some contact pitting but if it is not turned on way more than the average hobby shop I wouldn't think it would be an issue. The breaker shouldn't pop even with a 5 time overload for at least 500ms or so. The motor will draw more current with less restriction but it shouldn't be more than the FLA of the motor and if it will run without overloading the breaker (on a properly wired circuit) with NO pipe attached it shouldn't overload with any sized pipe attached.

[Michael Reinhart]

Thanks Van I will give it a try.

[Carl Beckett]

I wanted to convert due to the large draw on start up and would also like to up size to 6" duct and was told this would create more draw on the motor. Thanks for the fast response

Its not obvious to me that the larger inlet diameter would make a noticeable difference in startup current spikes. I would guess rotor/impeller mass would be the larger contributor (combined with magnetic slip effects of the particular induction circuit design)

The higher voltage would contribute better to lowering line losses (and resistive losses of the motor). But you can only switch voltage on motors that are designed for dual voltage operation. So unless your motor is listed as dual voltage - no you cannot swap. If yes, then its worth doing in my opinion. (a number of my machines have dual voltage windings and I always prefer the higher voltage).

Read the plate specs on the motor.

[Van Huskey]

Its not obvious to me that the larger inlet diameter would make a noticeable difference in startup current spikes. I would guess rotor/impeller mass would be the larger contributor (combined with magnetic slip effects of the particular induction circuit design)

The higher voltage would contribute better to lowering line losses (and resistive losses of the motor). But you can only switch voltage on motors that are designed for dual voltage operation. So unless your motor is listed as dual voltage - no you cannot swap. If yes, then its worth doing in my opinion. (a number of my machines have dual voltage windings and I always prefer the higher voltage).

Read the plate specs on the motor.

I don't think he was refering to the increase in pipe diameter effecting the inrush current, just that he wanted to minimize it.

I have never seen any demonstrable evidence that the higher voltage on a dual voltage motor increases performance, other than potentially a faster acceleration to full speed which isn't a factor on a DC or any WWing machine. If you have significant line loss resulting in voltage drops below the normal operating threshold of the motor that is certainly a different story. I am always open to new information and if you know of any either anecdotal or scientific I would indeed be interested.

[shane lyall]

I just ran....well, walked slowly,....I'm getting old. downstairs and looked at mine. I have the HF 2HP and it isn't listed on the plate to have a 220 option. I've never needed to get inside the motor so I don't know if it is possible. As Van stated, the short spike shouldn't cause you any trouble. I've checked mine with my Simpson and my son's Fluke meters with amp probes and can't even see the spike.

[Carl Beckett]

I don't think he was refering to the increase in pipe diameter effecting the inrush current, just that he wanted to minimize it.

I have never seen any demonstrable evidence that the higher voltage on a dual voltage motor increases performance, other than potentially a faster acceleration to full speed which isn't a factor on a DC or any WWing machine. If you have significant line loss resulting in voltage drops below the normal operating threshold of the motor that is certainly a different story. I am always open to new information and if you know of any either anecdotal or scientific I would indeed be interested.

Van - Im with you (I have designed induction motors in my past - from scratch - for use in pumping applications). In practice a number of factors come in to play, but the most significant is that in order to make a dual voltage design work you are effectively making a TRADEOFF instead of optimizing for a single voltage. But in high volume applications other compromises win out - like compromising the return flux path on the outside of the stator lamination to reduce size and minimize cost (you get more laminations per sheet of stamping, etc). Almost every production motor I have analyzed could benefit by increasing return path lamination cross section.

In my shop there are times when I am utilizing extension cords more than I should - and here I find the higher voltages to run better.

[Howard Acheson]

Shane, the plate on the motor would read "120/240 volts" if it is a dual voltage motor. If it just lists "120 volts", it is a single voltage motor.

Edit: The HF website says "2 HP, 120 volt, 60 Hz, 20 amp peak, single-phase motor". It's definitely a single voltage 120 volt motor.

[shane lyall]

I understand Howard but I'm saying mine is only listed at 120 volts. My old RAS is listed at 120 as well but after pulling the covers was an easy conversion. The dust collecter may be as well but I've never looked.

[Kevin W Johnson]

I've had the cover off of my HF DC, it's definitely 120 only.

I changed mine out to 6", swapped out the impeller to a 12" as well. I just went out and put the clamp meter on it to make sure my memory was correct. Running, it still only pulls 12.5 amps.

What's the peak start up draw in stock form?

[Van Huskey]

What's the peak start up draw in stock form?

My guess the inrush current peak will be in the 65-80 amp range, keep in mind this will only last for at most 150ms. Be aware to "see" this you have to have a meter designed to test inrush (even then the cheaper ones of these aren't very accurate) something in the mid-upper end of the Fluke 330 series for example.

[Kevin W Johnson]

My Fluke 337, shows me a peak of about 75 amps at start up. I was curious if it's much different than stock form. I don't think there will be a big difference, the running amps didn't much when I went to the 12" impeller, but it is having to move a heavier impeller at start up.

[Van Huskey]

Kevin, I see now you wanted an actual number and not a WAG, your Fluke does agree with my "WAG meter". A motor/blower is considered a "hard" start load. You almost certainly increased the inrush with a heavier impeller that will show the motor more load, but given the fact that inrush is hard for a meter to accurately display I think it would be very easy for the stock version to "test" the same or even higher. I would think the difference is small enough and the accuracy low enough that one would have to do them side by side, account for instantaneous voltage (or use a regulated supply) with the same meter. Even then I am not sure if the variance wouldn't be inside the margin of error unless you had a very sophisticated meter.