Re: [RE-wrenches] Two Load Questions

Alan; The ceiling fan problem is super tricky, and I'd be interested in what others say. The DC ones I used to install (and have here at my place) draw only 5 watts at low speed, and 10 watts at higher speed, with enough circulation to be pretty effective. Might be worth a small DC power supply. M

Re: [RE-wrenches] Two Load Questions

I've used FanWorks permanent magnet DC ceiling fans and they use very little draw and are available in 12 or 24.tap off a 48V battery bank or use a buck converter? http://www.thesolar.biz/RCH%20Fan%20Works%20DC%20Fans.htm Doesn't spin very fast at 12V but destratifying air doesn't take much mo

Re: [RE-wrenches] Two Load Questions

Probably very similar to what I have, Bill. They destratify air just fine at slow 12V, and are pretty breezy at 24V. I would NOT recommend center tapping a battery bank though, even at only 10 watts. A DC-DC converter would be far better. Dan Fink, Executive Director; Otherpower Buckville Energy

[RE-wrenches] LUX to STC conversion?

Off the top, can anyone tell me how many lux of sunlight represent 100% of STC? 1000 watts/sq meter? Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ List sponsored by Home Power magazine List Address: RE-wr

Re: [RE-wrenches] Two Load Questions

Alan, Ditto to Bills last post. I always require a load evaluation as it imposes a certain amount of personal responsibility on the part of the off grid customer. Two years from now when they call you and tell you they think there's something wrong with their system you can take that load form o

Re: [RE-wrenches] LUX to STC conversion?

Do yuo really want Lux? The formula is 1Lux=0.001496 watts/sq. meter Module performance is generally rated under standard test conditions (STC): irradiance of 1,000 W/m², solar spectrum

[RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

Why would one specify DC voltage appliances or lighting for off grid systems today when we have sub-buck-a-Watt PV solar power? If you have space, you can make the added power that conventional AC appliances draw for very low cost. It could even be argued that the cost for DC items, wiring, dis

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

The Sundanzers can be converted for AC use at the factory for a nominal cost, and they claim it affects efficiency very little. Chris Daum Oasis Montana Inc. 406-777-4309 406-777-0830 fax www.oasismontana.com _ From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

I for one like a DC light in my inverter room. Just sayin'... Brian Mehalic NABCEP Certified Solar PV Installer™ R031508-59 IREC ISPQ Certified Affiliated Instructor/PV US-0132 PV Curriculum Developer and Instructor Solar Energy International http://www.solarenergy.org On Tue, Dec 11, 2012 at

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

The light by the inverter is the only DC appliance I routinely recommend nowadays in off grid homes and businesses, unless they have no backup generator. If no backup, every electron counts, and there are some DC appliances, in that case, that can be worth the price and fuss. Blessings, Kelly

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

Hello Larry, I still install DC fridge/freezers in off grid systems for efficiency, but also so that when the owners leave for the weekend/week/month they can turn off the inverter and all the associated phantom AC loads, but the DC freezer is still on. When they come back, the meat in the fr

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

I'd do the comparison against one of the much cheaper energy star rated AC models. In my comparisons,On the slight edge in efficiency isn't worth the extra cost of the DC units. I've also had premature failures of DC fridges due to low voltage. Finally using the inverter's built in low volt

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

Hi Jason, With respect to you, Sub Zero is an exceptional refrigerator but at 4-5 times the cost of conventional high efficiency refrigerator so the cost comparison is not really relative to most peoples choice. A typical efficient 25 cu ft refrigerator will draw about 400 kWh annually. Thats

[RE-wrenches] micro v. string comparisons

Does anyone have any reports or data or studies that compare micro v. string inverter performance when there's a single unshaded roof plane? That is, a side-by-side comparison. We know that when any shading takes place that micro strings will perform better than a series string feeding into a

Re: [RE-wrenches] LUX to STC conversion?

I should’a knowd that phyxics just ain’t that simple, and now that you’ve sent me the formula, I need to go find out what AM1.5 means on a clear day in Kansas with a humidity of xx%. My brain gets fuzzier an fuzzier. Thanks Chris. Bill Dorsett Sunwrights From: re-wrenches-boun...@lists.re

[RE-wrenches] Pilot Hole Template

Hello, The roof I'm currently working on is not a typical roof. The construction is as follows: 2"x6" tongue and groove exposed inside, with 4 inches of foam (blue board) and on top of that 3/4" plywood with asphalt shingles on top of that. I'd like to make a template to ensure that my pilot bi

[RE-wrenches] Solar "PowerGrip" From OMG Roofing Products

Esteemed Wrenches: I was at the Midwest Roofing Contractors Association show last week in Grapevine TX. One of the vendors in the exhibit hall was OMG Roofing Products. Have any of you used this product? http://olyfast.com/product-details/product/PowerGrip.html?language=en *_Excerpt From

[RE-wrenches] Kee Safety "Solar Platform System"

Esteemed Wrenches: I was at the Midwest Roofing Contractors Association show last week in Grapevine TX. One of the vendors in the exhibit hall was Kee Safety Products. Have any of you seen or used this product?http://keesafety.com/images/uploads/us/documents/(D3)ASSEMBLYSOLARplatform_NA.pdf

Re: [RE-wrenches] PV String Over-voltage

I purchased one of these devices from AEE Solar about 2 years ago. It may not be in their current catalog but I am sure they still have info on supplier. It’s a temperature controlled switch in small outdoor enclosure that goes in line with one or more modules. If temperature drops below low

Re: [RE-wrenches] off-grid permitting problem

We have a client that just had assembled on his rural property a pre-fab modular home with "normal" wiring and 200 amp main panel and meter base. However, landowners around his property will not grant access for electric utility to cross and he needs to move in ASAP. He realizes that some day he

Re: [RE-wrenches] Pilot Hole Template

Jesse, I can't picture how you will use the flashing and EMT as a guide? 2x6 tongue and groove? So is it laid flat (interconnecting the T&G) or is it on edge like a truss? Either way, if you can establish a reference point from inside to the roof, then from the inside (if accessible) accurately

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

this brings up a probably off topic subject regarding efficiency. i have always considered efficiency and conservation to be job one... especially on off grid systems... but with modules so inexpensive... does this still make sense? for example, i have an off grid customer who i suggested get a

Re: [RE-wrenches] Remote relay options

Hello Howie, I use Jackson Systems (dotCom) wireless relays. Regards, Dean On 12/10/2012 7:14 AM, Drake wrote: Reviewing the posts, I agree that wouldn't help.  At 06:16 PM 12/9/2012, y

[RE-wrenches] Wind Turbine sources?

With news that Southwest Windpower has layed off some of its staff and that they are discontinuing the Whisper line I wonder who will pick up the slack, if anyone! Perhaps Bergey will make their XL.1 in 48V. What turbine brands can the wrenches recommend? Sorry if this does not pertain to this

Re: [RE-wrenches] DC, or not DC, Dat is Da question (Two Load Questions)

Conservation = doing without it. Efficiency = doing it but using less energy. We really always try to avoid specing any system that's DC only, but we get some pretty unusual requests from remote regions. The Morningstar SureSine inverter has made most DC system designs moot. But not all. Dan Fin

Re: [RE-wrenches] off-grid permitting problem

Jeff: There is a code passage that specifically states that one does not need to provide full rated ampacity to a service. I am sure you can find it. Find a way to prove, mathematically, that the system planned will provide adequate power. Create or find a spreadsheet listing all appliances

Re: [RE-wrenches] Pilot Hole Template

Jesse: How are you going to avoid crushing the foam when you tighten your fasteners? William Miller At 06:00 PM 12/11/2012, you wrote: Hello, The roof I'm currently working on is not a typical roof. The construction is as follows: 2"x6" tongue and groove exposed inside, with 4 inches of