Putting an LPS (Lightning Protection System) on a structure probably does attract more strikes. However, since a strike can happen to any structure, the one with the LPS is far better protected. NFPA 780 can get you compliant if you elect to install one.
Jimi Young - civilian
184th...
And add NFPA 70E to your research - it will give you safe clearance distances, arc flash boundaries and PPE requirements.
Jimi Young - civilian
184th CES/Electrical Shop
Ks Air Nat'l Guard
McConnell AFB, KS
Slow down boys! Stop...and read NFPA 70E! This is how you get dead. You need a coordination study done to determine available fault current, to get an energy incident rating (cal), which then is used to determine what hazard risk category (1-4), which determines your PPE. You need to have a...
Is there a non-contact medium voltage tester for use with a "shot gun" hot stick? I have 12470 volts at the load break elbow connections in the primaries of our pad mounted distribution transfomers. The load break elbows have an external grounding conductor, a bare solid #12, and they all...
We use Schneider Electric (Sq D) Power Logic metering on our 25+ facilities. We do the installs, use Ethernet or fiber and set it up on our network. The meters are also getting inputs from the water and gas meters as well.
Jimi Young - civilian
184th CES/Electrical Shop
Ks Air Nat'l Guard...
dpc - Thanks for the response. That's what I thought on the pvc issue and I get the term bolted now...Thanks
Jimi Young - civilian
184th CES/Electrical Shop
Ks Air Nat'l Guard
McConnell AFB, KS
About figuring fault current values on secondary distribution feeder circuits - I have a question. When plugging the type of conduit (PVC, RMC, etc.) into the equation do I enter steel or PVC if the conduit run has steel elbows only and mostly PVC?
I'm having an engineering outfit do the...
We have about 45 facilities each averaging about 30 emergency fixtures - predominately 2X4 T8 Troffers and as of late, T5HO pendants. Our problem is that 90% of them aren't self diagnosing so we do the yearly 90 minute burn test. We have about a 20% failure rate, about half of those battery...
I have a fire suppression water reservoir tank of about 65K gallons of water. We had about 120 gallons of diesel get into the tank. We have pumped it out a few times and have the vast majority of the diesel out. I'm trying to find out if there is a substance I can put in the tank to clean the...
I have a 400Hz Freq. Converter, 480V Delta input with a 208/120V Y output. Do I treat the Manual Transfer Switch located downstream as the Main - Grounds and neutrals bonded together. The freq converter is a seperately derived system is it not? After I get this cleared up then I have a question...
resqcapt19 - Thanks. Those are really the only things I could come up with, also - durability. What is your opinion of set screw vs. compression? Mine is that although I think set screw probably makes about as good a bond as compression and is a faster install, I prefer compression for the...
I want to change some of our "Standard Work Practices". I want to ban all die cast fittings and use only steel. Can the argument be made that the steel fittings are better, and if so, how? I know they cost more, but if I can get better bonding results then I'm OK with that.
It is true that the Base Civil Engineer is the AHJ on the base. The NEC does limit the "setback" to 1/4", as has been pointed out in this thread. However, AF standards/regs such as UFCs, AFIs, ETLs, and TOs often dictate overkill, whereas the NEC is always the minimum. Working on an AFB...
Thanks Guys...I guess I need to give more info to get a more detailed response. Both transformers are on our 12,470V power grid. On the loss of utility power to our Air Nat'l Guard base (which feeds these transformers) we have two 1.5 MW generators which will then feed one of the transformers...
I have a facility that has two sources of power available and want to put a transfer switch in. Each of my two sources are padmount transformers. Do I need overcurrent protection on each source - between the transformer and ATS?