GR1225 battery revert

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harleynatenv
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GR1225 battery revert

Post by harleynatenv »

We have a repeater on a mountain top that could use some more battery revert time. We are seeing about an 8 hour period before the battery can't run the pa, and thought about adding a second automotive deep cycle. Does anyone know if this will damage the charging circuits in the battery revert kit if both batteries get exhausted? The manual doesn't really say one way or another. I know it says you should charge up a battery with an external charger, but that just isn't possible in the winter due to site access.
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Bill_G
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Re: GR1225 battery revert

Post by Bill_G »

Welcome Harley. If you have power to run the existing radio with batt revert/charger option, then you'll have power to run an external charger. I don't see how the winter factors in.
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Bill_G
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Re: GR1225 battery revert

Post by Bill_G »

Here is the manual for the HLN9455 battery revert option -

http://www.repeater-builder.com/maxtrac ... essory.pdf

It discusses the power calculations you need to increase your battery operation time. It says the trickle charger is current limited (self protected), and thus will not be damaged by multiple batteries. However, it warns the trickle charger will not be able to fully charge large batteries, or large battery arrays, and recommends an external charging configuration. There are many battery charger/maintenance systems available on the market that can be sized to give you from hours to days of operation. Physical size, weight, input power, ventilation, and budget will be your limiting factors.

I hope that helps.
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jackhackett
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Re: GR1225 battery revert

Post by jackhackett »

I believe he was referring to the part of the manual that says the trickle charger is not intended to charge a fully discharged battery and you should use an external charger in that case, which could be a problem if the site is inaccessible due to winter weather.
RFguy
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Re: GR1225 battery revert

Post by RFguy »

We use the Xantrex TrueCharge 10 chargers with a single external battery, (or Truecharge 20 when we have 2 or 3 batteries) on our sites that have GR1225 repeaters. We often run 2 3, or 4 batteries in parallel. My favorite battery is the C&D BBG180RT which is a 100 amp hour gel/AGM type battery.
Don't use a "solar" battery as they are made for "cycle" duty, not a constant float charge.
Don't use wet cells.
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Bill_G
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Re: GR1225 battery revert

Post by Bill_G »

jackhackett wrote:I believe he was referring to the part of the manual that says the trickle charger is not intended to charge a fully discharged battery and you should use an external charger in that case, which could be a problem if the site is inaccessible due to winter weather.
Ah. Good point. The manual does say disconnect and charge which could be a problem when your ETA to site is three months (or so).

Reading between the lines that warning can also mean do not parallel an external high cap charger across the batt revert circuit.
harleynatenv
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Re: GR1225 battery revert

Post by harleynatenv »

RFguy wrote:We use the Xantrex TrueCharge 10 chargers with a single external battery, (or Truecharge 20 when we have 2 or 3 batteries) on our sites that have GR1225 repeaters. We often run 2 3, or 4 batteries in parallel. My favorite battery is the C&D BBG180RT which is a 100 amp hour gel/AGM type battery.
Don't use a "solar" battery as they are made for "cycle" duty, not a constant float charge.
Don't use wet cells.
Is that to say you don't use the internal power supply/charger package at all and just use a 12 volt dc source charged by the Xantrex? Or have you modified the revert kit to not charge?
RFguy
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Re: GR1225 battery revert

Post by RFguy »

harleynatenv wrote:
RFguy wrote:We use the Xantrex TrueCharge 10 chargers with a single external battery, (or Truecharge 20 when we have 2 or 3 batteries) on our sites that have GR1225 repeaters. We often run 2 3, or 4 batteries in parallel. My favorite battery is the C&D BBG180RT which is a 100 amp hour gel/AGM type battery.
Don't use a "solar" battery as they are made for "cycle" duty, not a constant float charge.
Don't use wet cells.
Is that to say you don't use the internal power supply/charger package at all and just use a 12 volt dc source charged by the Xantrex? Or have you modified the revert kit to not charge?
We install the standard GR1225 package complete with the GR1225 interna; power supply, battery revert and external battery. Then we simply add on the Xantrex Truecharge across the battery at the battery terminals. In effect there are 2 chargers, but as the chargers charge based on a constant voltage, the 2 do not fight each other.
harleynatenv
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Re: GR1225 battery revert

Post by harleynatenv »

Thanks RFguy. That's a great idea, I'm sad to say I overthought it. I have a couple of locations that would benefit from this. Thanks again.
com501
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Re: GR1225 battery revert

Post by com501 »

You should also consider running the radio at much lower than the recommended 25 watts in repeater operation, say around 10 watts. Makes it much more efficient.

I sure hope you aren't at a site with any other radios, though, since this is essentially a mobile radio gimmicked up.
BRadiomanSCA
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Re: GR1225 battery revert

Post by BRadiomanSCA »

I am about to utilize the battery revert (HLN9455) for my GR1225 repeater, which is to be on a mountaintop at a construction site and after reading the posts here am wondering now.............. does the battery revert supply 12V power to the repeater on it's own right? I'd thought and maybe I'm still correct in thinking that I need to put external battery supply power (12V), for the repeater/revert to connect up to. Having said that, if I use two (2) AGM type batteries, in 6VDC, tied together in series to create 12VDC I'll get a whopping 500 amp hours of back up. THEN...the question is, how much battery charger capability to use to keep these batteries 'floated', based on a 12 hour work day and probably 40 to 50% useage of the repeater, transmit/receive? Anyone?
BRadiomanSCA
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Re: GR1225 battery revert

Post by BRadiomanSCA »

Additionally, to my last post/question, the thought here is to provide battery charger and solar panels to power the charger, for the back up batteries (external) for the repeater, with the battery revert installed in it. So, the question again, is how much charger output would one suggest, for the charger, in order to float the AGM type batteries and how much draw will the charger have, to size the solar panels properly? Thanks all!!......................
JakePope
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Re: GR1225 battery revert

Post by JakePope »

BRadiomanSCA wrote:Additionally, to my last post/question, the thought here is to provide battery charger and solar panels to power the charger, for the back up batteries (external) for the repeater, with the battery revert installed in it. So, the question again, is how much charger output would one suggest, for the charger, in order to float the AGM type batteries and how much draw will the charger have, to size the solar panels properly? Thanks all!!......................
Using solar panels and battery system is the best..I have got similar problem and my charging problem is nearly solved
RayKing
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Re: GR1225 battery revert

Post by RayKing »

JakePope wrote:
BRadiomanSCA wrote:Additionally, to my last post/question, the thought here is to provide battery charger and solar panels to power the charger, for the back up batteries (external) for the repeater, with the battery revert installed in it. So, the question again, is how much charger output would one suggest, for the charger, in order to float the AGM type batteries and how much draw will the charger have, to size the solar panels properly? Thanks all!!......................
Using solar panels and battery system is the best..I have got similar problem and my charging problem is nearly solved
Yes it is but I am bit worried about prices.. Are they not touch expensive?
Sgt. Q
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Re: GR1225 battery revert

Post by Sgt. Q »

I am resurrecting this thread because I am wanting to do something similar, I am needing help to connect some solar panels to a HLN9455 Battery Reverter for one of our repeaters. I am Sgt. of Patrol for a small County Government in western Oklahoma. Since I have a background in electronics (Bachelors in Industrial Electronics) I have volunteered and been tasked with creating a solar battery backup system for our repeater. We had a recent ice storm which knocked out our entire communications system for the whole county. And to make things worse the cell phone system in the area went down as well. So as you can imagine, a complete lack of the ability to communicate with my Sheriffs office is not a good scenario for the residents of the county for any emergency services that may be needed. And we indeed to have a bad situation of a guy trying to kick the door in on a house with the residents inside. So it made a already bad situation worse.

So what I am wanting to do is connect a solar panel or two to 3 batteries ( in parallel). This system would also be connected to the HLN9455 battery reverter, so that when the ac line power goes out the battery reverter will switch to the batteries and the batteries can be charged by the solar panels. When the ac line power comes back on it would then switch back to ac line power. This is how the system operates normally, I am just adding more batteries and then a solar panel (or two) to keep them charged until power returns. What I am unsure of is if the solar panel being added is going to cause any issues with the battery reverter or repeater? Let me know what other info you need to help me. Although I have the bachelors in electronics, that was 10 years ago that I graduated. And I have not been in that industry for some time and I am a little out of practice. So please be easy on me with the technical jargon. Thanks!
Al
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Re: GR1225 battery revert

Post by Al »

On the design side the first requirement would be to select the required storage capacity for the battery bank based on how long your commercial power might be out and the expected power requirements of the GR1225 for that length of time. Once those variables are determined, you can then select the solar array size and charge controller that's necessary to keep the battery bank fully charged between commercial outages. A good place to start that would allow you to see what's available online to meet your requirements would be www.tessco.com.
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