I have a situation where I essentially need to suck air through a long section of ductwork and discharge it to essentially the atmosphere.
Suction pressure will be around 5 inches H2O and discharge pressure will be small, around 0.1 inch.
Let's say I take a fan rated for 500 CFM at 5".
If I...
I guess I should have stated: this is a refrigeration compressor. There was no real cost difference, the customer simply didn't know what he was doing when he ordered the system.
The compressor does not run when the truck engine is running, only gets plugged in overnight.
I had done a quick...
I have a customer who purchased a 3 phase compressor. 16Amp running load. Unfortunately, he has only single phase power avaliable.
I'm looking for a phase converter, but the trick is, this compressor (and converter) are on the exterior of a delivery truck. So, it will see vibration and rain...
FrankTech:
The real current of a new fan is ~12A as applied.
It does not run 24hours.
I'd say an average working day will be 12 hours spent on battery/alternator power (with intermittent off cycles, totaling about 3 hours of the 12) and 12 hours off the power supply (again with about 3...
FrankTech:
Your English is quite good, much better than my Dutch! I was mostly making fun of myself, because it's been so long since I thought of wave forms that I'm not sure if I need to remember or learn.
So, the SP-320-xx does not have constant current output but the SP-200-xx and...
Operahouse:
You might have caught in my last post (just a couple of minutes ago) that the holder itself was 14ga wire and I'd estimate the local air temps to be around 120F inside the enclosure.
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macgyvers2000
One thing I've noticed is that there isn't much out there geared towards...
Comcokid:
1&2: It is isolated through relays, when the ignition is moved to on, the "AC" relay is opens and the "DC" relay closes.
3&4: I originally tried a lower output power supply, but could not get the fan through startup (the power supply went into hiccup overload protection mode). I...
Forest through the treees:
I forgot to tell you that the load (DC fan motor) has failed several times. In fact, it seems that we can't keep it alive more than 2 months.
Several other systems have been installed for a while longer with other customers and neither failed a load or burned up a...
OperaHouse
Per the cataloge, the holder can be used with 30A fuses. I'm using a 20A fuse on a ~12A circuit.
I have noticed that the holders get almost to hot to touch whenever they're being used in a "high" current draw circuit. (We use them with fuses from 5A-20A, they only get that hot...
12VDC circuit. In line blade style fuse holder. Fuse/holder connection is very tight (difficult to remove fuse). 20A fuse.
When examining this system several weeks ago, I noticed that the fuse/holder showed signs of overheating (some plastic & rubber melting) with the link in the fuse...
Thanks all for the excellent information. The inverter manufacturer was concerned about the locked rotor current. The compressor manufacturer said that the start up current was less than the locked rotor current. I was in the middle scratching my head.
12 VDC - We can get 3phase compressor...
It's a compressor motor, about 1.5 kW. The motor is set by the compressor manufacturer, I'm just trying to determine if I can give the customer what they're asking for (ie: ability to start/run off the selected inverter).
I am a mechanical engineer with very limited AC motor experience, so please be patient with me!
I would like to run a single phase AC induction motor off a DC system via an inverter, but I'm worried about motor start.
The inverter is capable of 8.7 Amps continuous, 18.8A surge. Motor...
