
![]() Pulling a 400 HP, DC motor out of a lift today. Going into the motor shop for new bearings and cleaning. We do this every 5 years to prevent break downs. This motor weighs 4500 Lbs.
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![]() I had a close call yesterday, a wake up call for sure! I was troubleshooting a 490 volt control system, feeding an oil pan heater for a auxiliary drive engine on a ski lift at Purgatory. The thing was, the guy that wired it made a crucial mistake! He brought the hot 480 volt power leads in on the bottom and connected them to the bottom of the contactor! Major no no! You always bring the hot feeder lines to the top and connect them to the top of the contactor, it's the industry standard!! It's what we all expect. It's what we take for granted, that the top is HOT! Not the bottom. I made a mistake too...I broke the cardinal rule! 'Identify the source, then verify it dead' with your meter! I didn't do that. I had my meter out, and I checked things, but didn't verify the incoming hot leads! I thought the 'TOP' of the contactor was wired to the hot leads.....it wasn't! So, now I've got 500 volts AC, coming into the bottom...and I thought the power was off in the panel! Well, it turns out, I had a guardian angel that day, watching over me. I reached in and touched a screw that I was unhooking, and felt a little tingle in my hand...hmmm, was that a shock, I wondered? I grabbed my meter and started testing everything for power. To my horror, I realized there was 500 volts coming into the bottom of the contactor, HOT! The reason I only felt a tingle is the lucky part.... The line I touched had live power on it, but it was feeding through the bad heating element (the reason I was there) first, then to me! This reduced the power I got substantially. I hardly felt it! Had I touched any other wire, I would have gotten nailed! It was a bad mistake, one I won't make again! I have been reawakened! Lucky day for me!! Thank you, angels....Craig ![]() I wired in this pump control to the existing Munro pump control panel. System is controlled with a Hand/Off/Auto switch. In 'Auto', a Rain Bird irrigation controller signals the relay in the lower left of panel to start a pump, and stop it after zones cycle. Customer was having to turn it off and on manually, and asked me if I could do this. They were very pleased to have it! ![]() Another center pivot call yesterday. I truly love going out to the hay fields and helping the hay farmers. Big vistas, and cool machines! Got this one going fairly quickly. Just a plugged up end gun nozzle. That's it you see spaying in the center of the photo. The 'ole boys cooked steaks and potatoes and insisted I stay and eat, before they'd let me leave! ![]() Had a call to a home that the owners felt they were being over charged for power. They were seeing bills of over $200.00 a moth for a small home with little electrical usage. Water heater is gas, furnace is gas. I checked the actual 240 feeder lines amp draw and calculated the wattage and Kwh (kilo watt hour) usage. I estimated they would see around $96.00 dollars a month based on this reading. I Kwh = 1000 watts for 1 hour. I have inserted the method for calculating your own wattage from your meter using the formula shown. It's simple math, so don't get nervous. Follow the directions shown and you can figure out what you are using for the whole house, if you're interested. You will need your residential rates from your utility. Most have them posted on line. Ours here with La Plata electric is 11.3 cents/Kwh. So you multiply your watts product from the formula by .113. Pretty easy! The example here is 5400 watts. Remember to calculate the number of hours at that sustained rate too. It's a bit tricky to know how the usage is changing, based on what's being used, and for how long. That's the key to getting an accurate number. ![]() Working with a lineman here, de energizing a transformer that feeds one of the lifts. I had to work on a 480 volt disconnect, and we don't like working with it hot. So I had the lineman pull the feeder cables here. He's using a 'hot stick' and also wearing high voltage gloves, for added safety. The circuit he's working is hot 12,460 volts. The high voltage 12,460 comes in on the left, where he's working, and the low voltage from the transformer, comes out on the wires on the right. The transformer drops the high voltage from transmission levels, to working voltage levels, like 480 volts. This is a very common voltage used in industrial applications. This is also 3 phase power, 3 hot wires, Both on the high and the low voltage side. I had a call today about a repair for a sodium vapor lamp fixture used for a grow lamp. The guy had changed the bulb of course, and 'it still doesn't work', he said. I asked a few questions and determined that most likely, the ignitor had failed. Some gas bulbs, like sodium vapor, use an ignitor to 'ignite' or fire the circuit through the gas, and light the lamp. I recommended to him that he should replace the ignitor. Some folks call it the 'starter'. Anyway, I'm linking you to my favorite booklet for a ton of info on gas bulbs and troubleshooting them! Great info! http://media.hydroponics.net/productdocs/HID_Pocket_Guide.pdf ![]() Here is my good buddy, Loyd's ranch. He has 3 center pivots here, and he owns the mountain I'm sitting on, taking this picture! It's a lot of fun to go out to Loyd's to work on his pivots, it's very nice. He's in Tiffany, Colorado. Just past Ignacio, Colorado. It's about 1 hour drive for me from Hermosa, Colorado. I've been out 3 times already for problems this spring! |
Craig's blog
The life & times of my electrical world! Archives
March 2016
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