Generator backup at repeater sites

[neiowa]

NFPA____ says PSAP backup generator needs autostart/transfer. Anyone know if says anything in about what a repeater site requires?

In particular, does any section of NFPA ____ say a repeater site need a autostart/transfer switch on a genset? Many in our area don't even have genset just battery backup.

Regional grant has gensets but autotransfer switch are dang expensive and paging out to start the genset as required would be a high payback savings.

[nmfire]

Last time I read NFPA 1412 or whatever the number is, I do not recall seeing anything about it at all. The econo method is to use batteries to carry it until you can connect and start the generators manually. For a single repeater, the batteries will last a long time to begin with.

[islandfire03]

What we did for our remote receiver site was to buy several bus/ truck batteries and wired them to power a UPS so that we get 12 hours run time for the repeater in case of extended power outage. there is an auto conditioner charger that runs on 110 volt to keep them ready.
We have a portable generator that can be brought up and plugged in long before the battery back up goes down.
Our primary transmitter site has a auto genset as we are co-located in the counties radio hut and use their microwave for backhaul to the dispatch center.

PS. Make sure your repeater is purchased with 12 volt power supply capability. Not all have this or it's optional.

[LVFD301]

I will check when I am back in the office, but a basic Generac Genset, propane, that will run a repeater site, with auto transfer was less than 2k.

At one point I had nearly 100 Generac propane sets at tower sites, they worked very very well.

Under communications center in NFPA 1221 (which ISO went by when asking about our tower sites) 4.7.3.2 it states that the transfer shall be automatic.

Under communications enhancements, it states that IF the generator is there, ti should be automatic. 9.3.1.3.2.10

All have to be installed in accordance with NFPA 70 and 72.

[LVFD301]

What we did for our remote receiver site was to buy several bus/ truck batteries and wired them to power a UPS so that we get 12 hours run time for the repeater in case of extended power outage. there is an auto conditioner charger that runs on 110 volt to keep them ready.
We have a portable generator that can be brought up and plugged in long before the battery back up goes down.
Our primary transmitter site has a auto genset as we are co-located in the counties radio hut and use their microwave for backhaul to the dispatch center.

PS. Make sure your repeater is purchased with 12 volt power supply capability. Not all have this or it's optional.

On remote reciever sites, the power draw is normally very light, and batteries will work great. Very good point about the 12vdc power supplies, some of the 24 volt or 28 volt power supplies or backup systems (like the MTR2000 by Motorola) can be terribly expensive.

[nmfire]

I will check when I am back in the office, but a basic Generac Genset, propane, that will run a repeater site, with auto transfer was less than 2k.

At one point I had nearly 100 Generac propane sets at tower sites, they worked very very well.

Under communications center in NFPA 1221 (which ISO went by when asking about our tower sites) 4.7.3.2 it states that the transfer shall be automatic.

For PSAPs or for tower sites?

...(like the MTR2000 by Motorola) can be terribly expensive.

Surprise huh.

[LVFD301]

For PSAPs or for tower sites?


Surprise huh.

No part of the specs say PSAP nor Tower site. You get to interpet what they want.

[Seagravesstick]

According to my dealings with ISO, any portion of a communication system that requires power, also requires back-up power. If the back-up power is a generator, it shall transfer automatically, even on remote sites. It also shall notify the dispatch center when it is operating.
ISO Slayer

[neiowa]

Good point.

I'm finding that smaller autotransfer switch are not as outrageous to buy as I thought. In the $1200 range. Still seems totally wasteful use of $ when have 12hr + of battery power.

[islandfire03]

Good point.

I'm finding that smaller autotransfer switch are not as outrageous to buy as I thought. In the $1200 range. Still seems totally wasteful use of $ when have 12hr + of battery power.

neiowa: Go to Norwall power systems for good pricing on generators and auto transfer switches. Their in Arizona and ship free. I have bought several generators and transfer switches from them.