Impulse Heating of Sealing Bar

Hi Guy's,
I have a very old machine and wondering if anyone has upgraded the control for short duration impulse heater bars? The tranny is a 3phase 415VAC - 42VAC 4kW and currently it is a single SCR by the looks of it to give only half wave.
Operating voltage is around 20-30V @ up to 60-80A.

Wondering if changing to an SSR and control via a AB L3 plc would be the way to go as there are a lot of old cards that are no longer available that control the existing. I might even look at the new wire compounds as I am sure that these days the 400mm long wire would not need 4kW to seal meat bags.

I would contact Ropex:

http://www.ropex.de/

They have a very good impulse sealing solution and may be able to help.

Controlling just based on a fixed SSR or phase controlled relay solution doesn't provide very good results because it is hard to find a good balance between speed of temperature increase and desired final temperature. Thermocouple solutions tend to be slow responding unless you can get the thermocouple right on the heating element. Ropex uses the heating element itself to determine the temperature so it is very fast and very accurate.

Keith

kamenges said:

I would contact Ropex:

http://www.ropex.de/

They have a very good impulse sealing solution and may be able to help.

Controlling just based on a fixed SSR or phase controlled relay solution doesn't provide very good results because it is hard to find a good balance between speed of temperature increase and desired final temperature. Thermocouple solutions tend to be slow responding unless you can get the thermocouple right on the heating element. Ropex uses the heating element itself to determine the temperature so it is very fast and very accurate.

Keith

Click to expand...

Thanks Keith I have sent them an email with information and will see what they come back with. I see their controllers talk Ethernet/IP which is good. I am sure that we will not be needing 4kW to heat the sealing bar up so will be interesting to see what they come up with.

Cheers,
Steve