Solenoids On Automatic Machines Ac Or Dc?

[Anne Bonnys Locker]

I normally don't touch automatic machines but I just picked up 4 as new Daewoo DLS-600-ATT machines for next to nothing. As I do not have the computers or special motors I am going to use the electric foot lift bar to run the foot lift and thread cutter in one action but I need to supply power. Unfortunately the solenoids just give me voltage and duty cycle without mentioning AC or DC.

Unusually the web has proved useless. Can anyone point me in the right direction?

[gottaknow]

They are likely DC. AC solenoids hum and buzz when the solenoid is activated and held in the energized state.

Regards, Eric

[Anne Bonnys Locker]

Thanks Eric, AC would have been simpler for me.

I used to work for a solenoid valve company - Asco - and DC solenoids have the disadvantage of being larger. The "shading ring" in the solenoid is supposed to eliminate the hum.

[gottaknow]

Yeah, I have units I just use a bridge rectifier to convert ac to dc. I do have some knife actuators that are ac on my Brother 2 needle machines.

Regards, Eric

[Anne Bonnys Locker]

More confusion, thanks Eric

[Trox]

Hello Darren,

I do not know the machine type so I am speaking of leather sewing and upholstery machines in general.

For thread cutting you can use a electrical Dc solenoid. On the foot-lift you need more power and the DC valves are getting very big. You must use it together with the machines foot-lifts exchange rods to make it stronger. Or the best solution is to use air pneumatic cylinders, they are much stronger compared to size. If I was to use a DC solenoid for my 441 foot lift, it had to be as big as a start motor for a Mack truck.

Thats why most use air add ons on things like that, much cheaper too. Most already have a air compressor in their workshop too, then buy some waves, some hose, and air cylinders. Most compressors already have a reduction valve on it. You can use manual or electrical switches to activate them if you do not have a system motor.

Good luck

Tor

[Anne Bonnys Locker]

Hi Trox, the machines are pretty much a copy of a Juki straight sewer so big power isn't needed. The solenoids are already fitted and I just need to power them.

As the rotary foot lift solenoid is so small I am guessing it is AC.

[Trox]

Hi Trox, the machines are pretty much a copy of a Juki straight sewer so big power isn't needed. The solenoids are already fitted and I just need to power them.

As the rotary foot lift solenoid is so small I am guessing it is AC.

OK Darren,

they are already in there. If they are designed to be operated by a system servo they will normally not be on more than 24 V DC (from 5 to 24 V DC) in some cases 30V DC. This is the maximum out power from a normal control box I believe. I think you will see it if it is a AC solenoid, then it has a control cables from the motor in addition to the power supply from the 110/220 v socket. I do not know, I use air. They should have the operating power and markings on them, or some kind of number you can google to see the data sheet on them.

Darren, What is written on them?

[Anne Bonnys Locker]

There is almost nothing useful printed on them. The reversing solenoid just gives voltage (33V) and the duty cycle but nothing else including part numbers.

OK Darren,

they are already in there. If they are designed to be operated by a system servo they will normally not be on more than 24 V DC (from 5 to 24 V DC) in some cases 30V DC. This is the maximum out power from a normal control box I believe. I think you will see it if it is a AC solenoid, then it has a control cables from the motor in addition to the power supply from the 110/220 v socket. I do not know, I use air. They should have the operating power and markings on them, or some kind of number you can google to see the data sheet on them.

Darren, What is written on them?