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Utterpower PMG Field Testing One of our test sites is in the Central Mountains of Washington State. It gets cold, it's wet and miserable and even dry and dusty in the summer and fall. The test site is an off grid home occupied year round, the generator runs for 24 hours a day during the cold spells which last up to two weeks at a time. Average run time is 8 hours or more a day seven days a week, 52 weeks a year. I got a call from our test site about two weeks ago, the operator said the engine is running poorly, the valve lash adjusters have no more adjustment left, and he said he'd like to buy a new rocker Arm assembly. I told him to come on down, and by the way, bring the PMG so we can look it over and check it out. The generator is under a simple cover, no sides, and it's real close to a dusty road, the road is used by a number of people accessing their recreation properties during the summer and fall, so lots of dust. The operator runs the 6/1 to the point where it smokes, and then backs off just a little. He's retained the stock muffler, so the soot mixes with fuel oil, lube oil, dirt, dust, and other things to make a very effective grinding compound which covers the area of the generator. Running at the heavist load is normally the cause of lots of soot, but no maintenance, poor maintenance can do it as well. In this case, no lube at the ends of the pushrods, and failure to clean the carbon away is the likely cause of the Extreme wear of the open valve gear. Carbon, dust and grit gets into the push rod cups, tops of the tappets, and effectively grinds everything down. I'm sure the push rods are now a lot shorter, but we will let the operator make the call as to whether they need replacing and when.
Opps! you can see I started cleaning this fan cover before I took the picture! This is 10,000 hours worth of soot
Here's the fan, yikes! that's a lot of soot!
Pulley was packed with soot down in the grooves, original belt was a GoodYear Gator Back, 10,000 hours of service, belt looks shot to me, but the operator said: "No money in the budget for a new one, so we'll run it till we have the money, or it flies off."
In conclusion, had this PMG been a child, it would already be in the custody of CPS. Had the generator been an open frame unit like the ST Gen, there's little doubt in my mind that the fan would have pulled in all the highly abrasive carbon into the unit and likely destroyed it in the first 3000 hours. The Utterpower PMG's internals are sealed, and the unit is capable of surviving in all kinds of harsh environments. It is never a good idea to subject your equipment to more abuse than necessary, this site produces useful information to us as many do. After some effort to clean the PMG up, I found it took Dawn dish soap and lots of it to cut through this stuff, touch it, and it's all over you. Be interesting to know if the engine runs any cleaner, once lash is adjusted, but it could be timing and any number of other things. Operator has no computer, email, etc, so I guess I'll hear more next time I see him. There have been a number of problems with the engine, frozen and broken water jacket, water leaks not tended to, loss of coolant resultign in cracked cylinder head, and more. We put the PMG on the test bench. My power Analyzer saw all the readings exactly as new! This unit had a THD of 3.5% with a 2000 watt load at 60.00 HZ. The newer units have recorded as low as 2.9% THD with the same test load. More Field Testing: There are some very smart people who have taken all the mystery out of measuring the benefit of deployed technology in Africa and other Third World Countries. They look at the ability of the Village where this equipment is deployed, they measure their ability to use the technology to better their lives, AND to pay for the equipment deployed. This (in my mind) is an important piece of being realistic and embracing scientific principles. What good does it do anyone to deploy equipment that breaks, can't be maintained by the village, or can't produce a return on investment measured in any realistic terms? The truth is that many efforts to help in the third world HAVE failed to actually help the people. I feel privileged to know some who devote their life's energy to help people and to make a REAL difference. With this said, the PMG has been deployed on some of the platforms where it can be studied and the benefit measured, fact is, it may be a while until we know the outcome, but there are no failures or problems noted so far.
Above: Engineering Student 'Alison Ferris' installing a PMG as part of an EWB (Engineers Without Borders) project in Uganda.
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