What Size Circuit? - Hammer A3-31 Jointer/Planer Or N4400 Bandsaw w/ 4HP Motor

[ben_r_]

Rod Sheridan has a lot of posts about the electrical requirements for, and other aspects of, his Hammer A3-31 and is very knowledgeable about the machine, and I reviewed his posts when deciding to make the purchase. 
If you Google "Electrical requirements for Hammer a3-31," that thread it the first thing that comes up.  It was started in 2010 but continued in Feb. 2017.  As of 2010, he had been running on a 15A circuit for 2 years with no problems and said he could have used 20A but not 30A because the equipment manufacturer specified the max for its equipment.  He's in Canada and follows Canada code requirements.  I will try to get his attention and see if he has any interest in weighing in here.
    I stated this in the original thread, but now that we have a dedicated thread, I will reiterate that I am running on a 30A circuit, but had a 20A subpanel made that is attached with magnets to the back of the A3.  It was quick and easy for the electrician to do, and it has worked without a hitch.  I got the idea from a Youtube video posted by Thomas Gadwa.  He has several showing how he tricked out his Hammer.  "Power service connection for Hammer A3 31"
  Hope this helps.

Rod Sheridan states in the "Electrical requirements for Hammer a3-31" thread mentioned above that Felder warns that you should not use a 30 amp receptacle for the A3 31.  Well, Delaware technical support told me yesterday and again 6 months ago to use a 30 amp circuit.

Others have said that the breaker protects the house wiring, not the machine.

So...figuring that we really need a definitive answer on this I called Felder/Hammer a third time.  I spoke to Phillip in the Delaware tech support area (866-792-5288).  Again he verified that a 30 amp circuit is preferable, but that a 20 amp may work.

I asked Phillip to send me an email stating what he told me over the phone to avoid any warranty issues should the need arise.  He agreed to send it.

Here is what Phillip from Felder/Hammer tech support wrote:
"Thank you for contacting us regarding your Hammer A3-31 with a 3kW power system. As we discussed on the phone the specifications for this machine call for 230v single phase power plus or minus 10%, and the machine will be the most efficient and have the greatest service life operating closer to the 230v spec than at the outer edges of this range. Voltage lower than 230v, the starting of the machine, and eventual deterioration in efficiency as the machine ages will all cause some increase in current consumption compared to a new machine running at 230v. I am not a licensed electrician and can not make determinations for what should be installed in your shop - only a qualifed, licensed electrician in your area can do that. The machine's specifications recommends a 20 Amp circuit breaker as that will provide just enough for the machine to start and run, however to have some extra room on the circuit for other devices, to future proof for eventually upgrading to a larger machine, or just to avoid operating so closely to the 20A cutoff if you have voltage within the 10% range below 230v, it is acceptable from our perspective to install and use a 30 Amp circuit instead as long as your local codes and licensed electrician allow.

Please remember that the design of this single-phase, capacitor-start electrical system requires that you press and hold the start button until the motor is up to speed, then release. The stop button may be quickly pressed instead of held. This procedure will ensure the longest possibly life for your capacitors. Failing to hold the start button until the motor is up to speed will cause premature failure of these capacitors."

I like it! Thanks RobBob for taking the time to call in and get that email sent. When I get my A3-31 I guess Im going to be running a new 30A circuit for it.

 

[egmiii]

I'd run 10g wire and use a 20 amp breaker. The larger wire size will reduce the voltage drop, thus reducing current. It will also permit a 30 amp breaker if you need to go that route. Using the 20 amp breaker will offer some motor protection, but will also provide a heads up that other problems may exist if it starts popping.

 

[rljatl]

After all this talk, I went to the shop this afternoon to use the A3 31 in jointer mode.  It never ceases to amaze me how smooth and quiet the machine is.  I have the silent cutter head and can whole heartily recommend it.

My shop is in the garage.  I was running both the Laguna Pflux 3hp (has egg crate foam for sound insulation inside the cabinet) and the Hammer A3 31 at the same time.  Both on 30 amp circuits.  No one in the house was even aware that I was using the machines!  With ear muffs on, I had to keep looking at the cutter head on the J/P to make sure it was running.  I live in a townhouse so sound is important.

 

[Mismarked]

It is amazing. That is good information you obtained.  Thanks for doing that

 

[Rick Christopherson]

There is always a lot of misinformation on this topic, which is mainly due to differences between the NEC, manufacturer's directives, and reality.

The NEC typically specifies circuit requirements that are well above the "reality" of woodworking equipment. For that reason, I will Not address NEC ampacity considerations. I don't agree with them, but neither could I advise not following them. Consult with an electrician as to what the local requirements may be.

Manufacturer's directives are typically all over the map, with some manufacturers known for requiring circuits larger than necessary, to others requiring circuits smaller than required. Without looking at a case-by-case basis, this is typically the least reliable information.

What I will say, in this particular case, specifying a maximum circuit size of 20 amps is in contravention with the NEC tables. That's not to say that a 20-amp circuit is insufficient, only that it shouldn't be stated as a maximum.

On the opposite extreme, I have seen some manufacturers specifying minimum circuit ampacities that are well above the NEC tables. Again, that's not to say that having an over-sized circuit is bad, just that it shouldn't be listed as a minimum.

Personally, I prefer to take the approach based on the realities of how woodworking equipment is used in real life. In that regard, human-fed woodworking tools rarely ever see maximum load, and even then, is very short duration. They also experience significant no-load idle-time between cuts and operations.

But conversely, some woodworking tools may experience very frequent re-starts compared to running or idle time. Any tool that experiences frequent restarts without down-time, should be placed on a larger than typical circuit. The high-amperage start current will heat the circuit conductors (and breaker) more than a continuously running machine.

My reality is that I don't want to work with wires that are bigger and stiffer than necessary, yet of sufficient size to never trip a breaker during normal usage. If a 20-amp breaker never trips, then there is not a reason to have used a 30-amp breaker. So I base my circuit size on the motor's nameplate amperage, because I know that the motor will very rarely ever even reach that amperage, let alone exceed it for any length of time.

 

[rljatl]

[member=191]Rick Christopherson[/member] - Thanks Rick.  That's what we need to know; based on a realistic, practical perspective.

So, my interpretation from all of these sources is that either a 20 or 30 amp breaker is fine for the A3 31 as long as it is in agreement with your local code.

 

[ben_r_]

Rick makes it sound like speaker amplifiers. Which makes a lot of sense. These machines spend more time starting up or idling than they do anywhere near their max current draw from a max out motor.

 

[Richard A.]

The best way to protect your motor would be to use a starter with heaters.
Use a 30A circuit breaker.
Run #10 wire from the panel to machine (that includes any rubber cord or flex).
Note: If the run is over 100ft from you panel to you machine, run #8 wire, but keep the 30A circuit breaker.
Mount a 30A starter on your machine.
Install headers in the starter. The heaters should be sized to the amperage on the nameplate.

 

[Rod Sheridan]

Hi, Rick has given some good advice on breaker/wire sizing.

I live in Canada, and at the time I purchased my A3-31 and B3 Winner, the certification agency required that the machine not be connected to larger than a 20 ampere circuit, or one capable of delivering more than 5,000 amperes.

I actually have both machines running on a 15 ampere circuit (not simultaneously).

As Rick indicated, wood working machinery that's fed by people will spend the majority of time at idle, with some time at somewhere between idle and full load. That's why the Hammer motors are S6 40%, they recognize that the machines are typically hand fed, or if a feeder is used, it's still similar to hand fed operation where you pick up a piece, machine it, put it down, go get the next piece.

I often use the feeder for sawing, shaping and jointing if I have a lot of pieces, or need it for precision or safety. I've used the feeder for making flooring for example, which is the most severe duty I've ever used the machines for.

The N4400 is also mentioned, however based upon personal experience it won't start on a 15 ampere circuit, it will however on a 20 ampere. It's a pretty high inertia load, and the one I have appears to have a capacitor run motor, not capacitor start, and doesn't seem to have a centrifugal switch either.

When I asked Felder Ontario about the issue, apparently the new machines don't have the 20 ampere restriction, they do have different electrical equipment and layout than the older machines I own.

regards, Rod.

 

[andygiddings]

Have a C3 which is obviously a B3 and A3 bolted together. Motors are the same size. I use 30A breaker and my supply is 240V measured, never had an issue