Thread: Power for a Hammer K3

Not sure why people worry about start up current. The start up current would only last for a few seconds and so would probably need to be 100-200 amps to trip a 15 or 20 amp breaker in that time.

Originally Posted by Bohdan

When a single phase motor starts, a starter winding in the motor is energised via a capacitor. This starter current is only required for a brief time to get the motor up to speed.

It is commonly switched off via a centrifugally activated contact in the motor but these switches are unreliable and often need maintenance.

It appears that Hammer may be using the start button to control it. You release the button and the start winding is turned off.

You only need to hold it in until the motor is up to full speed.

Derek, you should be doing the same with the A3 31, and most probably the BS, given that it has the same motor.

I have never bothered holding the switch on my single phase A3-31 and it hasn't blown up yet and the saw is three phase. What is the experience of others?

When I got my Hammer N4400, I was instructed by qualified electricians to run a "15 amp" dedicated circuit back to a 20 Amp circuit breaker to accommodate any fluctuation in start up amperage. I also use 32 Amp rated power cords, that I got thru my sparky mate. He checked everything before allowing me to play with then then new toy.

Electrickery only gives you 1 chance, so I get my stuff checked by suitably qualified mates, before modifying anything. Yes I am lucky to have mates like that, but then again, my life is worth more than a couple hours/days of not being able to play.

Hi Paul,
Was wondering if you had one of the AR extractors? if so, how do you find it?

Cheers
Elliot

Originally Posted by ejw1234567890

Hi Paul,
Was wondering if you had one of the AR extractors? if so, how do you find it?

Cheers
Elliot

Hi Elliot

Still not sure how these threads are managed and whether this is where I post a reply - anyway, and assuming it was my earlier mention of a Felder Dust Extractor you are asking about, I have the Felder AF16 extractor which is one of the smaller ones they produce. It's the only one I've owned so I can't compare to anything else. Bought it as part of a package deal with the Hammer gear I bought. What can I say - it does the job. Initially I was a bit disappointed about the amount of the dust that was left suspended in the air after a workshop session. I finished up reducing that dramatically just by ensuring that at every connection was screwed down extra tight - I even ran duct tape around the junction points. All good now.

Cheers

Paul

Originally Posted by DomAU

Not sure why people worry about start up current. The start up current would only last for a few seconds and so would probably need to be 100-200 amps to trip a 15 or 20 amp breaker in that time.

It depends on the breaker being used.
A B rated Breaker can handle 5x its current rating for about 12s, or 100 A for a 20A breaker
A C rated Breaker can handle 10x its current rating for about 5s, or 200 A for a 20A breaker
A D rated Breaker can handle 20x its current rating for about 2 s, or 400 A for a 20A breaker.

After those times the tripping currents are the same for these breakers.
A 20 A breaker can even handle 40A for about 150s.
This all assumes the wiring can handle it as well so the wiring must meet the maximum currents the breaker can handle.

Starts up currents are not the same for all machines of the same power rating as it depend on initial load. My 3HP DC has about double the start up current of my 3HP TS, the difference being that a DC impeller starts having to move a full load of air whereas all the TS has to move is the blade.

thanks paul

Our club has a Hammer K3 winner which we love. Many members use it but I'm sure not all hold the ON button for any length of time. May have bearing on my next statement however. Just to swap the thread completely around, our saw won't stop . We can try each of the stop buttons (the main switch, the 2 emergency switches or the slider switch) but only the wall switch will stop it. We're currently seeking advice as noone in the club can read Austrian. Has anyone encountered such a problem?

I have no idea but it should be locked out if it isn't already.

You can try using Google Translate with your phone camera on the manual if you cant find an English one online. They speak German in Austria though. There is no Austrian language. Good luck.

Major issue if the emergency stop switches don't stop it

Has someone screwed around with the wiring?

The emergency switches should be interrupting power directly

Originally Posted by pippin88

Major issue if the emergency stop switches don't stop it

Has someone screwed around with the wiring?

The emergency switches should be interrupting power directly

Mine hasn't got an emergency stop on it but it does have an isolation switch to access the blade.