I have Building

[SuperBuickGuy]

Re: I have Building

Okay, now I have an electrical question. Can you run to 200 amp power panels off one 200 amp meter base?

[N20Silverado]

Re: I have Building

Okay, now I have an electrical question. Can you run to 200 amp power panels off one 200 amp meter base?

You will need to set a 200A breaker at the meter base and then feed the 2- 200A panels off of that. You have to limit the current to 200A to protect the 200A meter base. If you were to feed both 200A panels right off of the meter you would be able to draw 400A @ the meter base.

Like this SQ D- QOM2-2225NRB or equal

http://ecatalog.squared.com/pubs/Circuit%20Protection/Circuit%20Breaker%20Enclosures/Industrial,%20NEMA%20Type/1100HO9905R401.pdf

[SuperBuickGuy]

Re: I have Building

Who would have the problem - the power company or the electrical inspector?

[SuperBuickGuy]

Re: I have Building

The capacity to use more would exist; but as my workspace is moving from the garage to the shop; the actual use would remain the same.

[milner351]

Re: I have Building

The first thing I did when I purchased the property where my shop is located - was to update the electrical.

I went from 100amp overhead to 200amp underground. I got a new meter base, new 200amp 42 space square D panel for the house, and promptly filled nearly every space just with what the previous owner had wired into the 100amp 24 space panel!!!! (rats nest of wires)

I then ran a 100amp breaker from the house to the shop - where I installed a 100 amp service panel.

I have 220 outlets for a 7.5hp compressor, welder, vehicle hoist, used oil furnace, etc. Plus a ton of 20 amp outlets and many 15 amp lighting circuits.

I've never had an issue with the 100 amp capacity in the shop - even having multiple people working on different things simultaneously.

Unless you plan on setting up a serious powder coating oven operation or running several welding machines at once - you can save yourself a pretty penny buy sticking with 100 amp to the shop. I saved quite a bit buying square D breakers on ebay too!

[SuperBuickGuy]

Re: I have Building

It will be easy to wire a 200 amp breaker into the whole system to prevent overload; and between my 220v mig; 220v arc/tig; mill (to be purchased soon) and other machining tools; auto lift; and potential engine dyno.... I'm pretty much stuck putting 200 amp service in. My worst case is I'll have to wire a 400 amp meter base onto my house.... I know, I'm an energy hog.

[DanStokes]

Re: I have Building

Tell me about the dyno!! That's my area of expertise and maybe I can steer you in the best possible direction. Let me know if you want input.

Dan

[milkovich]

Re: I have Building

I was in the same boat as you, I was obsessed with having 200 in the garage, finally due to budget constraints I caved and upgraded the house from 60 to 200, and a 100 sub in the garage. They were going to bill me at a different rate if the garage had it's own panel, and the electrician that upgraded the house said I could only run half of whatever the house had (no idea why, must be our codes here).

So far I'm running a 30 amp mig, a 60 amp (peak) tig, a 20 amp (I think) two post lift, a 5 hp compressor (30 amp?), and a plasma cutter.

You can only use so many tools at one time before you're just showing off, even running the compressor, overhead lights, and plasma cutter I have yet to trip a single breaker. I wouldn't sweat putting a bridgeport and phase converter in there at all.

On an aside, I understand why guys love machine tools but I guess I'm spoiled because I know several machinists. I'm jonesing a tirechanger and balancer with all my heart... I'm sick of paying these guys $15-$20 a wheel for a mount/balance/disposal etc every time I buy more wheels and tires. I think those two machines can pay for themselves (I change crappy old wheels like women change shoes).

[SuperBuickGuy]

Re: I have Building

Dan - thanks for the offer... perhaps a basic primer on dyno operation would benefit more then just me? from my understanding a dyno is an electric motor which creates drag on the test motor.... for me, I'm more concerned about putting real-world drag on a motor to break it in; and to find problems while they're still relatively easy to fix.... not so concerned about the number it would show.

Milk - guys showing off? we wouldn't dream of doing such a thing ;D The tools you list approximate what I'm going to use; but what I've found is the cost difference between 100/200 is really almost zero.... right now I'm trying to save 500 bucks, thus that's the basis of my 200 amp question.

[N20Silverado]

Re: I have Building

Who would have the problem - the power company or the electrical inspector?

The problem is in protection. A breakers/fuses only job is to protect the wire and electrical equipment from being overloaded. If you were to connect 2- 200 amp panels to a 200A meter base would lead to the potential of 400A of current flowing through the 200A meter base. The inspector would catch it quickly and make you put in the item I talked about or upgrade to a 400A meter base. (But you would still need 2- 200 amp breakers at the 400A meter base to protect the wire going to each 200 panel)

Here's what I have in my house.

I have a 200A panel in my house and a 100A panel in my shop. The feed to the shop is only 60A. So even though i have a 100A panel I only have 60A capacity.

I would recomend at least a 100A to the shop BUT the only time I have ever had a problem is in the winter time. I have an electric furnace and an electric unit heater and when they both run together it will trip the 60A breaker. Both those items were scavaged from a jobsite and were unplanned additions to the total load.

I have a 7.5 HP air compressor, TIG, MIG, plasma and have never had a problem when using those items.

If you were already planning on 2- 200A panels I would stick with that plan. Steel, aluminum and copper are all down right now so it won't be as expensive as it was to go ahead and put in the larger services.

I will say this, I have never wired a dyno, so I don't have any real world experience with its operation or electrical load.

Tim

[SuperBuickGuy]

Re: I have Building

I don't have a problem putting the extra fuse in the system. I suppose I could simply replace the 200a meter with a 320a and be done with it - the costs are almost identical... 76 for the D square panel; 100ish for a 320a meter base... the other option would be to put a 2nd meter next to the house - but again, the "problem" would be the requirement of a disconnect at the meter since the panel will be 110 feet away..... again, lowest cost solution is my goal.

I'm seriously considering doing this in two stages... wire the shop to the house and my 50a welding plug.... wiring the sub-panel/meter base/etc then connecting it together.

I should say that one of the major reasons I'm insisting on 200a is I've seen what happens when a mill loses power while turning steel.... in fact I bet I still get some of my iron content from that result....

[N20Silverado]

Re: I have Building

I don't have a problem putting the extra fuse in the system. I suppose I could simply replace the 200a meter with a 320a and be done with it - the costs are almost identical... 76 for the D square panel; 100ish for a 320a meter base... the other option would be to put a 2nd meter next to the house - but again, the "problem" would be the requirement of a disconnect at the meter since the panel will be 110 feet away..... again, lowest cost solution is my goal.

I'm seriously considering doing this in two stages... wire the shop to the house and my 50a welding plug.... wiring the sub-panel/meter base/etc then connecting it together.

I should say that one of the major reasons I'm insisting on 200a is I've seen what happens when a mill loses power while turning steel.... in fact I bet I still get some of my iron content from that result....

If you go the 320A route, you will have to set a 400A panel next to it and install 2- 200A breakers in it to protect the wire going to each 200A panel. This route is quite a bit higher in cost than what you think. Remember, you have to protect the wire and equipment with at breaker.


Oh, yea don't forget to compensate for voltage drop on your feed to your new building. You will need to upsize the wire . It is way to late for me to do the math right now. I will post up after some sleep.

Tim

[SuperBuickGuy]

Re: I have Building

I was thinking that I should run the power from the meter into a 200 amp box; then run power to each panel - the house/the shop. I can get away with an indoor panel. By running it that way; it would be impossible to draw more then 200 amps through the meter. The wire to the shop will be 110 feet....

[DanStokes]

Re: I have Building

A bit of info on the dyno - I should send you a Xerox of my old dyno article from January 2000 HRM. There are a number of types of engine dynos. Possibly the best for home shop use is a hydrokinetic (water brake). They'll absorb a lot of power for their size and are, in most cases, the cheapest. They take almost no AC power but do require a pretty large quantity of water, which is used as a heat sink. Power has to be dispersed into SOMETHING. Some folks have taken a large plastic tank (500 gallons or more) and used that for the water source.

Superflow makes the best known water brake but there are others out there. I haven't worked with Stuska but I understand that they make water brakes and a similar dyno that uses oil of some type instead of water. If buying a used water brake, tear down the absorber section before you buy it - it looks a lot like a torque converter inside. They are known to eat up the absorber housing and/or impeller with aluminum oxide if the water wasn't properly treated and/or if the dyno wasn't stored correctly.

If you want to go with electric absorbtion you'll probably want an Eddy current dyno. It absorbs a lot of power for the money but cannot motor the dyno - usually not an issue for anything but emissions testing. The engine will have to be fitted with a starter because the dyno can't push the engine to start (same for a water brake). Most still require water to absorb the heat as it's difficult to feed power back into the grid to get rid of it. Eddy currents turn engine power into AC power and AC power into heat that's dumped into water to disperse it.

DC or flux-vectored AC units can motor the engine as well as absorb power but are crazy expensive and complex. I can't see any reason to dig into this technology for what you want to do.

Remember that in all cases the dyno is only the opening ante. It's only going to be as good as the instrumentation. At a minimum you'll need a load cell (should come with the dyno), an accurate speed meter (don't count on your engine tach), and oil pressure and water temp gages (automotive type should be fine). From there on, the sky is the limit - AFR instrumentation, perhaps by the cylinder, combustion gas analysis, etc, etc. There's no end and each one gives you valuable info that you didn't have before. And a dyno takes calibration and maintenance if it's to remain useful and accurate.

Midwest Absorbers is a good source for used/rebuilt dynos. I also have a friend who deals in used emissions gear and he often has access to dynos that have been removed to make way for newer gear or sometimes from labs that have gone under. I've been tempted myself but I really don't have the space or the situation to put it all to work.

Aren't you sorry you asked?
Dan

[SuperBuickGuy]

Re: I have Building

Thanks Dan... not sorry I asked - I'll have to search about for the HRM mag article. You mention 500 gallon water tank... wonder how irritated the enviro folks would be if I just used the creek behind my house?