2 hand control for press

2 hand control for press
Hello everybody i have a punching press with hardwired relays.

i am looking for the 2 hand control and antirepeat diagram hardwired with timer.
please help me.

Try looking into Nolatron.
their two hand anti tie down works great.
it also gives you what your looking for

i will look in my can library to see what i have.

regads,
james

gaannesh said:

2 hand control for press
Hello everybody i have a punching press with hardwired relays.

i am looking for the 2 hand control and antirepeat diagram hardwired with timer.
please help me.

Click to expand...

Why don't you use a 2-hand safety relay?

safety relay is very expensive and there is no local manufacturer.
it cost around 500 USD.

thanks Mr james
if you find please post the hardwiring circuit.

gaannesh said:

safety relay is very expensive and there is no local manufacturer.
it cost around 500 USD.

Click to expand...

It will cost you or your company much more if, God forbid, someone loses an arm.

that's why i want to implement safety control 2 hand

google "nolatron" and you will find several modules for use.

google two hand anti tie down and you will get a host of information.

i am trying to get ready for an 2 week project install next week and i cannot remember the wiring.

regards,
james

left parallel to right switch go to timer.
gorelay (will give a pulse) on series from left and right and not timer.

both switches need double contacts.
so you must press left and right within the timer
the pulse can be taken over by hold relays untill press is down

LadderLogic said:

It will cost you or your company much more if, God forbid, someone loses an arm.

Click to expand...

Truth!

dwoodlock said:

Truth!

Click to expand...

Will in some countries!

Hardwired Two handed controls for presses have been out there years before PLCs or Twin Button Safety relays existed.
This type of control did NOT cause the loss of limbs or life.
1. the buttons are/were normally snap action
2. they have both a N/O and a N/C contact
Normally the buttons are used to either close a guard OR
run the press for the first 160 degrees (past trapping/closing point)
the Press then returns to TDC via its rotary cams (usually two or three)
the N/C contacts are checked to prevent the next cycle as previously mentioned.
with a fully mechanically guarded Press the human risk is considerably reduced.
the major issue is with Light Curtains.

-

As far as the twin button controllers
I understand the concern for a maximum delay time to press the both buttons - might be a good idea
BUT
this is impossible to use if there is more than one operator starting station.

Even with Cat.4 (SIL 3 I think) the aim has always been to prevent the mechanical jamming of one button then cycling with ONLY One button.

It is all in the timing


http://www.plctalk.net/qanda/showthread.php?t=334

Just to avoid misunderstanding
"THIS TYPE OF CORRECTLY WIRED CONTROL"