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Shear wont run when it gets hot outside.

I gotcha diggerdoug, I'm trying to keep my guys with sheared parts and press braking them, I'm not sure how to spray Freon out of can, but definately an idea.

I do have a infrared gun, so that is what I
m using.
 
How does the shear know it is warm outside? Can it see the open door?
Can of freeze spray on some components can help.
Not a fan of Accurpress. When I was looking for a multi axis press brake they were one on the companies I called. Salesman had breath that could kill a skunk. I kept moving away. Guy was no friend of a tooth brush. He never quoted me. Checking into their machines I found a number of complaints where there was a problem and factory guys could not fix.
And some factory guys are very well trained in "Billable Hours". They will make your machine right if it takes your last penny.
 
Not a fan of Accurpress...
...Checking into their machines I found a number of complaints where there was a problem and factory guys could not fix.

Shop that used to bend my parts before I bought a new press brake had the same scenario. They even had me leave a sheet of my material, as they wanted the factory guys to run my parts, since it always worked fine when the factory guys ran their 'test program.' This went on for months.

I like the sales guy for them in my area - he sells other lines of good stuff, but the main reason he could tell me to buy Accurpress over something else is that they have service guys all over the place in my area, whereas the machine I ended up buying would need to be serviced out of Chicago.


That said, I'm betting the problem is power related more than Accurpress related, in this case.
I just checked output legs on the phase converter, made up phase is running 237 volts and the shop power is running at 118 Volts, when the shear motor is running / but not cycling the made up leg shows 210 volts.

Is that 210 measured line to line (as in, we'd expect it to be 237)? I'm no machine tech, but if that's the case, that's where I'd be looking. If you're measuring line to ground, then 210 would be expected from an RPC, but since you compared it to 237 under no load I'm thinking it's line to line, and that doesn't seem high enough.

I'd be looking at low voltage before temperature. Temperature may play into why the voltage is low, but the symptom sure seems to be voltage.
 
I agree with Fish On, your using a 40 H.P phase converter that can pull as much as 250 Amps at around 100ish amps output.
Now I realize your not pulling the full 100+amp output so your input amps will be less as well, but the odd voltage reading you come up with confuse me a little. Measure your input voltage leg to leg and check the output voltage leg to leg during the shears complete cycle operation. Re confirm after the shear quits working. Make sure there's no power beyond control systems operating off the generated leg. I would also check the amperage draw during shear operation on all 3 legs on the output of your phase converter, if out of spec check the 2 input legs amperage draw during load. you could be experiencing phase converter lag. Your press brake more then likely pulls far less amperage then your shear.
 
Yan Wo, No my shop is not air conditioned.

Fish On, Those electrical readings were all from leg to ground.
So when there is no load on the made up leg it shows 237 volts, when I turn the shear on it drops down to 210 volts
 
Yan Wo, No my shop is not air conditioned.

Fish On, Those electrical readings were all from leg to ground.
So when there is no load on the made up leg it shows 237 volts, when I turn the shear on it drops down to 210 volts

If you can do it without reversing a motor, swap the made up leg with another lead at the machine. Perhaps the more reliable voltage will keep systems going.

Another possibility is go to the shop very early (say, 4am) on a (to become) hot day, check the voltages at the time, then run the machine and see if it's reliable. At least, that will indicate whether it's a voltage issue, not just a heat issue.
 
I agree with Fish On, your using a 40 H.P phase converter that can pull as much as 250 Amps at around 100ish amps output.
Now I realize your not pulling the full 100+amp output so your input amps will be less as well, but the odd voltage reading you come up with confuse me a little. Measure your input voltage leg to leg and check the output voltage leg to leg during the shears complete cycle operation. Re confirm after the shear quits working. Make sure there's no power beyond control systems operating off the generated leg. I would also check the amperage draw during shear operation on all 3 legs on the output of your phase converter, if out of spec check the 2 input legs amperage draw during load. you could be experiencing phase converter lag. Your press brake more then likely pulls far less amperage then your shear.

Until your confirm without a drought that input power is not the source of your problems and then testing for correct oil/hydraulic pressure at given test points during operation at the time of machine malfunction you are basically pissing in the wind.
 
What about all your connections and rocker switch in the foot pedal. They could heat up and not work properly. Faulty overloads, old breaker, faulty contactor?

Sent from my SM-G960U using Tapatalk
 
With all this chatter about electricity I tend to get confused. I thought the original scenario was;

Push the pedal.. hold downs extend and all works perfectly

Push the pedal..the hold downs hesitate a few seconds, then all works perfectly.

Push the pedal..nothing works!

I don't quite see how this could be an electrical problem, in my experience, electrical is either 'it works or it doesn't work'..no sort-of-works!

Sort-of-works is more of a pneumatic or hydraulic phenomenon..spool valves or solenoid valves or pressure relief valves, but not electricity.

I'm going to guess the coils on the hydraulic solenoid valve are either 120 volts or 12 volts or even 24 volts. This seems like it would preclude any glitch in the RPG supplied voltage.

I could be totally out to lunch on this, but we'll see what develops.

Stuart
 
Agree with atomarc here. The easy way to eliminate the electrical controls is to energize the control solenoid with a separate power source when the machine is acting up. If machine still goes not work then the control system is eliminated as a possible problem. If the machine does work then some part of the control system is failing and just need to focus in more and find it.

It is also possible the generated leg off the RPC is being used in the control circuit, and the odd voltage of it is doing funny things. I dont think that question has been answered, unless I missed it.
 
Perhaps way off base but has the temp of the hydraulic fluid been checked?
Have ran into the bypass not flowing as it should, overheating the fluid and binding the valve.
Only would show up in elevated shop temps as otherwise it was running ok on the ragged edge.
As I said this one rare and out in left field. Trades fix in one case was to pack dry ice around the oil tank when it was hot in the plant.
Bob
 
Perhaps way off base but has the temp of the hydraulic fluid been checked?
Have ran into the bypass not flowing as it should, overheating the fluid and binding the valve.
Only would show up in elevated shop temps as otherwise it was running ok on the ragged edge.
As I said this one rare and out in left field. Trades fix in one case was to pack dry ice around the oil tank when it was hot in the plant.
Bob

Yup, that's what I have been trying to have the OP doo, sort out first if it's oil breaking down, or the solenoid coil getting weak from heat.
 
Process of elimination is always the best way to diagnose machine problems.
Yes I suggested basic testing of the phase converter output voltage under load power, it should take all of 10 minutes if you drag your feet. Reason, eliminate any concerns of voltage drop, phase converter lag etc. I have seen failing coils, shorting contacts under load creating voltage drops, etc,etc. Then on to any of the electrical control sytem componets to confirm correct operation. Control coils can and do act up due to heat. And yes this is most likly a hydraulic problem, but we always start testing with the what ever drives the system and move on from there once everything is confirmed correct. As I stated in a eariler post Test pressure gauges in the correct circuits of the hydraulic system will tell a world of needed information. If it is infact a overheated hydraulic circuit (Doubtfull) then the correctly placed pressure gauge will show low system pressure do to some componet in the system dumping pressure. I don't personally know of any shear with a oil temp pressure relief, Why wood they. A couple of inexpensive Pressure gauges a few fitting and hose will show if correct control valve action is occurring. Test gauges with a safety margin above your shears standard working pressure would be all you need.
Guessing will get nowhere, I can't recall ever spending more then a couple hours chasing a electrical/hydraulic problem in our equipment.
 
Yup, that's what I have been trying to have the OP doo, sort out first if it's oil breaking down, or the solenoid coil getting weak from heat.

I'm betting on the solenoid getting hot and not working
or a relay getting hot and stopping. maybe a powersupply

could take a box fan and blow air up the skirt of the thing
see if that keeps it working.
might work and isn't keeping the thing working what counts.
 
I'm betting on the solenoid getting hot and not working
or a relay getting hot and stopping. maybe a powersupply

could take a box fan and blow air up the skirt of the thing
see if that keeps it working.
might work and isn't keeping the thing working what counts.

Or a simple dollar store squirt bottle, fill with water, put it on mist.
 
Some one talked about the oil getting hot, that is definitely not the problem, it was barely warm to the touch and the oil system was flushed thinking it was a sticky valve and a new 55 gallons of oil was added.
I'm thinking based on everything I've read is its a coil problem.
 
Some one talked about the oil getting hot, that is definitely not the problem, it was barely warm to the touch and the oil system was flushed thinking it was a sticky valve and a new 55 gallons of oil was added.
I'm thinking based on everything I've read is its a coil problem.

I wrote about both getting hot, and how to eliminate 1 or the other.

So now you have eliminated 1.
 
I have a 1989 Accurshear 25010, meaning it will shear 10' of 1/4" plate.
I've been plagued with this problem since I bought it used from Roush Racing 5 or so years now.
The problem is that when it warms up outside, it quits working, I will use it for 15 - 30 minutes, it will run normal, then I will hit the pedal and it will start giving a delayed reaction before the hold down pistons come down allowing it to shear.
So, the motor will start up and run just fine, nothing changes with that, its just when I hit the pedal, it wont respond, the plungers wont come down and it wont shear.

I've had the authorized Accurpress repair guy, he changed the pumps and other valving, when he left it worked just fine, but same thing, it failed on a warm summer day, so he said I should replace the oil and do a flush, I did that, with same results, I had my electrician out that works in control panels in industrial plants all over MI, he couldn't find the problem.
I dont use the shear everyday, but I do use it on a consistent basis through out the year and this only happens when its warm outside and it been doing this approximately 5 years now.
Can you manually push in the pilot valve when it locks up? The voltage should be 24v coming in at that location. I have seen if undervoltage would cause it to have enough power to engage the coil. I’m assuming this does not have remote hold downs or independent control hold downs correct?
 








 
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