New PowerPro Issues

[trubio]

I talked to Dave at Shopsmith customer service yesterday, Jan 24. I asked if it was normal for the PowerPro to get hot when operating at 10000 rpm. He said "It can get pretty darn hot".

I then explained that it got especially hot along the top along the main shaft. He said that's right and to make sure to keep the drive hubs on as they can act somewhat as heat sinks.

I then told him about how I had been running almost constantly at 10000rpm for about 45 minutes and then noticed that my display read "Inverter Heat" and how I shut it down and opened the access hole and cooled it down with the vacuum.

He said he had never heard of that message(Inverter Heat) before and he put me on hold and went to check with someone else. When he came back, he told me that 45 minutes is the maximum time that they recommend running the machine at high speed and that it would be normal for that message to appear in that situation. He said I did the right thing by shutting down and opening it up.-- That's what they recommended.

I also asked him if he could tell me the meanings of some of the abbreviations(SRM, RPS, PFC, IGBT) in the troubleshooting section of my manual. He didn't know what they meant either. I mentioned that it would be nice to know what they meant. He said he would bring it up at the next meeting.

After hanging-up, I realized that it would also be very nice to explain somewhere in the manual about the heat issues and "Inverter Heat" display and the recommendations about operating at high speeds.

I called back and he had gone to lunch, so I gave the message to Jan and she said she would let him know.


Today I did a little more thinking and reading and testing.

First of all, after reading through the "Troubleshooting" section of my manual again, I noticed that in at least two cases ("Low Voltage" & "PFC Fault") the possible "solutions" include removing the belt cover and motor pan and allowing the machine to cool for 30 minutes.

This just verifies the obvious.-- Heat build-up can be a problem, especially for the electronics in an enclosed case.

Then I decided to measure the wattage consumed by my machine. I hooked-it up to the outlet through a little gizmo called "Kill A Watt". This is a little device that can measure and display volts, amps, watts, Hz, VA, PF and kWh. It probably isn't accurate enough for the National Bureau of Standards but I would doubt that it's more than 10% off. Anyway, it can give me a pretty good idea of the power consumption. I Found that my PowerPro is consuming approximately this much power at these speeds: 150w/2000rpm; 350w/5000rpm and 850w/10000 rpm.

This is all without any load and the machine just sitting there turning the shafts. If I take a block of wood and push it against one of the hubs to create a load, the power goes up over 1100w at 10000rpm. This would generate about the same amount heat as a small electric heater.

So, I think that the heat generated is normal considering how much power is going into the headstock and I don't think there is a problem with the amount of heat being created, but there is just not enough ventilation.

I have my little muffin fan hooked-up and it's always on when the power cord is plugged-in and for now I think I'm satisfied that I'm doing the best I can to minimize the heat build-up. I will try to keep an eye on things and if I'm not happy in the future, I will look at other possibilities.

[Ed in Tampa]

Trubio
You are right heat will kill electronics fast. You muffin fan idea sounds like a winner but I wonder about dust infiltration.

Your SS is working in a dusty conditions and the fan is bound to pull in more.

I wonder if it would not be better to seal the unit then place a fan and inlet hole with filter in a way that air flow is over the motor and electronics. If the inlet had a filter you could prevent dust from entering the headstock.

I also wonder about a sealed headstock and an external heat sink.

I suspect the heat issue is going to become more and more of an issue as dusty coats the heat sink and more people start using the power pro for production work where is it on more than casual home hobbiest work.

If 45 minutes of full speed is all SS recommends then I would not consider the SS power pro for shaper work. Once a big consideration for me tor shift to the power pro. As most shaper work that I do is takes longer than 45 minutes.

[algale]

He said that's right and to make sure to keep the drive hubs on as they can act somewhat as heat sinks.

As far as heat sinks go, wouldn't it make sense to mount either a sanding disk or a turning faceplate?

[JPG]

As far as heat sinks go, wouldn't it make sense to mount either a sanding disk or a turning faceplate?

Yes, but, IMHO depending upon a hub as a heat dissipator is wishful 'thinking' at best!

I understand the need to get it all in the existing headstock, but fear the previously existing heat issues have been greatly increased.

I do not think we have heard the last of this.

[robinson46176]

Some time ago I had talked about using a blower similar to the one in the link below and adapting a lawn tractor air filter to it. I have no idea where that discussion is now. I was just going to mount it at the rear hole.

http://www.surpluscenter.com/item.asp?item=16-1433&catname=


.

[charlese]

trubio - Thank you very much for posting you heat problem and the results from your call to Shopsmith. It is all good knowledge to have! These headstocks are much different than the older units and have their own unique issues. The more we know, the better.!

I personally would not have guessed the wattage used would be so high. Now I wonder about the claims from Shopsmith that the PowerPro uses less electricity.

Thought on fans - a small fan mounted to an open inspection plate, blowing outward, may be a good idea.

[dusty]

Quote: I then told him about how I had been running almost constantly at 10000rpm for about 45 minutes and then noticed that my display read "Inverter Heat" and how I shut it down and opened the access hole and cooled it down with the vacuum.

He said he had never heard of that message(Inverter Heat) before and he put me on hold and went to check with someone else. When he came back, he told me that 45 minutes is the maximum time that they recommend running the machine at high speed and that it would be normal for that message to appear in that situation. He said I did the right thing by shutting down and opening it up.-- That's what they recommended. End Quote

I wonder what the response would have been if you had said you'd been working for 60 minutes.

[robinson46176]

Thought on fans - a small fan mounted to an open inspection plate, blowing outward, may be a good idea.

Bad move. You would create a vacuum inside of the headstock and suck in an unbelievable amount of sawdust from every hole... You need to create a + pressure inside of the case using clean air. Then no sawdust can get in since it would be blown away from any leak point.


.

[nuhobby]

Quote: I then told him about how I had been running almost constantly at 10000rpm for about 45 minutes and then noticed that my display read "Inverter Heat" and how I shut it down and opened the access hole and cooled it down with the vacuum.

He said he had never heard of that message(Inverter Heat) before and he put me on hold and went to check with someone else. When he came back, he told me that 45 minutes is the maximum time that they recommend running the machine at high speed and that it would be normal for that message to appear in that situation. He said I did the right thing by shutting down and opening it up.-- That's what they recommended. End Quote

I wonder what the response would have been if you had said you'd been working for 60 minutes.

Good one!

I do remember during the initial PR ads for PowerPro, they cited the machine running an endurance test on the 12" planer, cutting an immense linear length of rough oak planks over the course of some days. But it didn't say how often they stopped and rested.

[JPG]

. . .
I wonder what the response would have been if you had said you'd been working for 60 minutes.

They would have said it had been displaying for 15 minutes, but you had not noticed!:D

Question is, what would the smell be with 15 min more?:rolleyes:

P.S. Why are not all the possible 'error' messages published and corrective action for each? How many more 'surprises' are there? If the 'inverter heat' condition was exceeded(>"45" minutes), why was it 'allowed' to continue running up to the scent threshold?

P.P.S. Do realize the '45' minutes was an after the fact estimate("about 45 minutes") in post #1. Like Dusty, I wonder what time duration was previously determined as a limit, and at what load/ambient temperature(We be doubting Thomas's for sure). I would expect such a response from Dave. Wonder who he 'consulted'. I do hope it was not J Mc! If not, I hope he has been made aware!