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Hohokam
Jun18-10, 10:08 AM
Hello all,
This is my first post so forgive me.

I am currently doing a internship for a wine company in Molina, Chile. They currently have a problem with the electricity; at 19:00 or so, the electricty company shut down the power, and they have to manually turn on the diesel generators for electricty. Now my objective is to find a way to eliminate the delay in power from the company to the generator also to remove the manual factor.

If you can point me in any direction that would be fantastic

Thanks,
Hohokam

dlgoff
Jun18-10, 05:47 PM
What you are looking for is a Automatic Transfer Switch (http://www.transferswitch4less.com/series300.htm) like this (depending on your load):
http://www.transferswitch4less.com/img17.gif
You can google and get lot of places that sell them.

Hohokam
Jun18-10, 10:18 PM
What you are looking for is a Automatic Transfer Switch (http://www.transferswitch4less.com/series300.htm) like this (depending on your load):
http://www.transferswitch4less.com/img17.gif
You can google and get lot of places that sell them.

Will it match the frequency of the previous input?

dlgoff
Jun18-10, 10:39 PM
Does your generator match the frequency the way you're using it now? I assume the way you are doing it now is, once the power goes off, you start the generator and manually switch to it, then bring the wine company's equipment back on-line. The automatic transfer switches I've used, sense the power outage, start the generator, delays to allow the generator to come to speed (voltage), then transfers the power to the load automatically.

hisham.i
Jun19-10, 08:41 AM
What you want is a system that starts the generator when the power is down, and shut down the generator when the main power is on..
You can do such a system using a relay, which switch on the motor starter if the main source is off, and starts on motor shut down system when main source is on.

russ_watters
Jun19-10, 09:15 AM
Note, a generator takes time to start so if you want a completely seamless transition, you also need an Uninterruptable Power Supply.

dlgoff
Jun19-10, 03:51 PM
What you want is a system that starts the generator when the power is down, and shut down the generator when the main power is on..
You can do such a system using a relay, which switch on the motor starter if the main source is off, and starts on motor shut down system when main source is on.
Here are the delays that are built in to the ATS I linked:
* Adjustable time delay to over ride momentary normal source outages to delay all transfer switch and engine-starting signals.
* Transfer to emergency time delay. Adjustable from 0 to 5
minutes for controlled timing of load transfer to emergency.
* Retransfer to normal time delay. Adjustable to 30 minutes.
* Five-minute unloaded running time delay for emergency
engine generator cool down.
* Four-second time delay to override momentary to ignore
momentary voltage and frequency transients during initial
genset loading.
And as russ suggests, if you don't have a UPS between the transfer switch and your load, you going to have some down time. In some cases this might be okay if your process can stand it since the cost of a UPS large enough to maintain 100s of amps would be high. I'm not sure how critical or how big of pain in the butt it would be to restart motors, etc. in the OPs wine company.

mheslep
Jun21-10, 02:59 PM
If the event that the diesel generators have to be replaced at some point, you might look into a fuel cell - natural gas option. The diesel + transfer switch is far cheaper than anything else at ~$0.50/Watt (http://www.emergencypower.com/standby-generators/standby-generator/) in upfront capital cost, so for truly occasional standby power that is the most economical choice. However, in this case the OP states outages are a daily occurrence so diesel fuel costs, pollution, and noise may dominate. The technology has not even been close in the past, but now in the event of regularly unreliable utility power and a cheap natural gas (or biogas) supply, a full time fuel cell (http://www.bloomenergy.com/products/data-sheet/) may be worth a look, especially a couple years from now.

Hohokam
Jun21-10, 03:33 PM
If the event that the diesel generators have to be replaced at some point, you might look into a fuel cell - natural gas option. The diesel + transfer switch is far cheaper than anything else at ~$0.50/Watt (http://www.emergencypower.com/standby-generators/standby-generator/) in upfront capital cost, so for truly occasional standby power that is the most economical choice. However, in this case the OP states outages are a daily occurrence so diesel fuel costs, pollution, and noise may dominate. The technology has not even been close in the past, but now in the event of regularly unreliable utility power and a cheap natural gas (or biogas) supply, a full time fuel cell (http://www.bloomenergy.com/products/data-sheet/) may be worth a look, especially a couple years from now.

We are actually working on installing solar panels now, so that help delay the usage of the diesel. You also have to understand that I am working in Chile so, changing the diesel generators for fuel cells is a little bit drastic. I very well could propose it but I doubt they would change any time soon.

mheslep
Jun21-10, 05:59 PM
We are actually working on installing solar panels now, so that help delay the usage of the diesel.
I'm not sure how that helps your company at 19:00 hrs. Batteries? Probably cheaper to charge the batteries from the diesels. You also have to understand that I am working in Chile so, changing the diesel generators for fuel cells is a little bit drastic. I very well could propose it but I doubt they would change any time soon.It certainly would not pay to change out the diesels before their expected lifetimes. If, an only IF, they happen to be near end of life I believe it is worth looking into. Of course the fuel cells don't care where they're located; they don't require a short maintenance tether to the factory as far as I know. They do however need an inexpensive gas source (I think propane also works) to pay off against the diesel fuel. If you have that, and I have no idea about gas availability in Chile, then FC's may make sense for a daily electric power source.