WHAT SIZE 12V RADIO BATTERY?

[Pelagic]

With these Orions, what I have trouble understanding is the difference between a 24 to 12 DC-DC CHARGER and a DC-DC CONVERTER
both 30a if kept on all the time?
The Charger applies power in 3 phases, bulk/absorb/float
The Converter balances to float???

[smac999]

The Orion smart (Bluetooth) models are 3 stage dc to dc. Programmable via Bluetooth.

Chargers must be connected to a battery. They can not directly power loads.

A dc to dc converter can directly power a load. Ie run a 12v vhf off a 24v battery. With no battery in between. Some dc to dc can also charge a battery. But if single stage is not the best solution. A charger would be.

[Bycrick]

Several people have made exactly my point. If you use the converter and leave the radio battery connected "all the time," the radio battery will either take forever to charge (converter adjusted to float voltage) or will be on absorbtion voltage even when fully charged (which isn’t good either). Supposedly, the battery charger version will handle that by reducing the voltage when the radio battery is fully charged.

[rslifkin]

Originally Posted by Bycrick

Several people have made exactly my point. If you use the converter and leave the radio battery connected "all the time," the radio battery will either take forever to charge (converter adjusted to float voltage) or will be on absorbtion voltage even when fully charged (which isn’t good either). Supposedly, the battery charger version will handle that by reducing the voltage when the radio battery is fully charged.

If the converter is big enough, the radio battery should never really get discharged at all if it's kept powered all the time.

[Bycrick]

You miss my point.

If the converter (which outputs a fixed voltage) is "big enough" that you never draw down the radio battery, then you don’t need the battery at all. It only adds weight, complexity and cost. You adjust the converter to run at the radio;s speced voltage of 13.8 volts. All good.

If you use the converter, then you have to choose a single output voltage. The SSB radio is speced at 13.8 volts input. So, do you set the converter at 13.8 volts? Will the battery like that voltage all the time? If you draw down the battery, it will take a long time to recharge at 13.8 volts.

[Bycrick]

When one writes in a hurry, clarity usually sufferers. So, upon reading the last post, I’ll try again.

There’s nothing in this system that is really 12 volts.

Most SSB radios have a design voltage input of 13.6 to 13.8 +/- 10%. If it’s a marine/commercial radio, it almost always has an internal power supply that drives the high-power final amplifier at about 40 volts. So it’s less sensitive to low input voltage. Most ham radios drive the final amplifier at whatever the input voltage is. That results in significant power reduction when run at less than 13.6 volts. It’s a severe enough problem that when hams run "portable" stations, they’ll often use an up-converter to take the "12 volts" up to 13.8.

If you connect your radio directly to a "12-volt-battery," the highest voltage you’ll see, ever, is about 12.7. That’s right at the very low edge of the design tolerance, which isn’t a good design point.

Now you have to keep the battery charged. To run the radio at its design point, you have to have an external supply at 13.6- 13.8 volts. At that point, the battery supplies nothing, and is constantly being "floated" by the external supply. That’s usually NOT a good idea, because when the battery is really "fully-charged" it will outgas even at 13.8 volts.

If, by some chance, you actually run down the radio battery, it will take forever to charge at 13.8. If you look, while it’s possible to trickle charge batteries at very low currents for a long time, they generally last longer when charged for at least part of the charge cycle at a higher voltage. So reducing the fixed-voltage converter output from 13.8 doesn’t really improve things.

If I were doing this project, I’d take one of two approaches:
1. The radio is going to run off the house battery using a down-converter set to 13.8. There’s no battery backup.

2. If long-term, or emergency, backup is critical I’d use a 100-200Ah battery, with a real charger from my house bank and then use an up-converter to take the battery voltage up to a regulated 13.8 volts.

[Pelagic]

Originally Posted by Bycrick

You miss my point.

If the converter (which outputs a fixed voltage) is "big enough" that you never draw down the radio battery, then you don’t need the battery at all. It only adds weight, complexity and cost. You adjust the converter to run at the radio;s speced voltage of 13.8 volts. All good.

If you use the converter, then you have to choose a single output voltage. The SSB radio is speced at 13.8 volts input. So, do you set the converter at 13.8 volts? Will the battery like that voltage all the time? If you draw down the battery, it will take a long time to recharge at 13.8 volts.

That for catching this

I think the supplier's Victron consultant who happed to be on lockdown in South Africa had a brain fart when he insisted on isolated and converter Orion for my radio battery supply. (I should have read the manual first)

Seems I have 2 options:
Exchange the unboxed convertor for the Orion smart DC-DC Charger
Or

Wire so the Converter normally bypasses the standby radio battery and adjust output voltage to suit consumers.

Weekly Monitor 12v radio battery and with selectable switch to converter, boost to float level when needed

I am discussing other aspects with Victron engineer in Holland, so will bring this up.

EDIT,
Bycrick....Just read your last post....
Will check SSB voltage requirements and review with Victron

Thanks!

[Bycrick]

Note. I have my Icom ham rig running directly from the house batteries. So the only way it will see more than 12.7 is when I’m running the motor or it’s too hot to go out in the noonday sun. I do mostly Pactor and run the radio at max 60%. It works fine. But since you’re designing this from scratch, I thought I’d throw my penny's-worth in. If you’re using a ham radio, it will never put out near rated power at 12,6 volts. Ever. But it may be enough. A marine radio will work fine on a 12 volt battery, but not if the battery voltage drops very much.

[s/v Jedi]

A lot of confusion going on here. The Smart Orion series can be programmed for either battery charging or fixed output power supply modes.

So what you have can do either

[Pelagic]

Originally Posted by s/v Jedi

A lot of confusion going on here. The Smart Orion series can be programmed for either battery charging or fixed output power supply modes.

So what you have can do either

Went back and checked my revised order and unpacked box to confirm.

Order was changed to 2 x Orion -TR Smart 24/12/30-A (360W) Isolated DC_DC Chargers

Duh!!!!

[sy_gilana]

12v 100Ah Maintenance free plus a fat ass capacitor sold in auto sound store for peak loads like SSB. LiFePo4 can also work in this role, but constant charge might kill it.

[Pelagic]

Originally Posted by s/v Jedi

A lot of confusion going on here. The Smart Orion series can be programmed for either battery charging or fixed output power supply modes.

So what you have can do either

I am having a problem finding a Deep Cycle 12VDC 100AH here in the Philippines, (no stock)

They still have stock of less popular, GEL batteries

http://handtoolph.com/dj-scorpio-gel...ilippines.html

is the best I could find

Never heard of them, but data seems ok and I am assuming the Orion -TR Smart 24/12/30-A (360W) Isolated DC_DC Charger can be configured for GEL?