Hi I am installing a Bose Companion 3 (Seriers 2) 2.1 speaker set up for my ipod in my hunter 23. I am looking at a new battery and inverter just for this (maybe a light or cell phone charger sometimes) I know a little about aH and such but not a bunch, the system is set up for 120V (50/60 Hz) but no amps or wattage. I called bose and they said 96 watts was peak, does this seem right? .8 amps?!?! I was thinks at around a 50 aH battery but is that nessicary and I was going with a 800 watt inverter, too big too small? SUggestions? Help? Thanks all -Jeff
Amp hour question...
- Thread starter SweetTrade
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Power (watts) = voltage x current
Use this simple equation to calc your needs. Example: 95 watts = 12 vdc x ? amps or 95/12 = 8 amps ( what Bose told you is correct but for 120VA, not 12 V) You'll draw 8 amps/hr off the battery for a 50 amp battery (shouldn't draw down below 50%), you have 25 useable amps prior to recharge being required or about 3 hrs of music minus whatever else you draw off the battery. If you substitue an inverter for allowing the stereo to operate off 120VAC, you STILL have the same current draw but with the added inefficiency of the inverter so your ACTUAL power drain when using an inverter will be greater than 8 amps/hr Make sense?
Use this simple equation to calc your needs. Example: 95 watts = 12 vdc x ? amps or 95/12 = 8 amps ( what Bose told you is correct but for 120VA, not 12 V) You'll draw 8 amps/hr off the battery for a 50 amp battery (shouldn't draw down below 50%), you have 25 useable amps prior to recharge being required or about 3 hrs of music minus whatever else you draw off the battery. If you substitue an inverter for allowing the stereo to operate off 120VAC, you STILL have the same current draw but with the added inefficiency of the inverter so your ACTUAL power drain when using an inverter will be greater than 8 amps/hr Make sense?
Whew, lotsa variables here . . . .
If you properly asked and Bose properly answered, you'll need ~100 W peak just for your stereo. You'll probably not run it at peak all the time so lets assume you'll run 50-75W. If that is all the AC you'll be running, a 300W inverter should be plenty. The inverter has ~ 80% efficiency so rounding up, you'll need 100 W into the inverter. That 100 W will require 8 Amps from your battery. If you follow guidelines to not exceed 50% of your battery capacity, you'll need about 40 Ah to run this for 4-5 hours and that puts your battery at about 80 Ah; a typical group 27 deep cycle will do it and leave some for other minor and occasional 12VDC loads.
If you properly asked and Bose properly answered, you'll need ~100 W peak just for your stereo. You'll probably not run it at peak all the time so lets assume you'll run 50-75W. If that is all the AC you'll be running, a 300W inverter should be plenty. The inverter has ~ 80% efficiency so rounding up, you'll need 100 W into the inverter. That 100 W will require 8 Amps from your battery. If you follow guidelines to not exceed 50% of your battery capacity, you'll need about 40 Ah to run this for 4-5 hours and that puts your battery at about 80 Ah; a typical group 27 deep cycle will do it and leave some for other minor and occasional 12VDC loads.
Is this sound system for your boat
or for the entire marina? A 110 piece symphony orchestra produces about 10 watts of acustical energy when playing fortisimo. And you are proposing a 95 watt system on a 23 foot boat? It should knock the barnicles off the hull.
or for the entire marina? A 110 piece symphony orchestra produces about 10 watts of acustical energy when playing fortisimo. And you are proposing a 95 watt system on a 23 foot boat? It should knock the barnicles off the hull.
it will last longer
if you don't turn it all the way up all the time. Also, beware running it off a modified sine wave inverter. It will probably induce noise into your sound system. Recommend using a pure sine wave inverter for stereos. Also, a pure sine wave inverter will run 90% or better effeciency. When you add it all up, it probably makes sense to put in a DC stereo system but thats up to you.
if you don't turn it all the way up all the time. Also, beware running it off a modified sine wave inverter. It will probably induce noise into your sound system. Recommend using a pure sine wave inverter for stereos. Also, a pure sine wave inverter will run 90% or better effeciency. When you add it all up, it probably makes sense to put in a DC stereo system but thats up to you.
I have an appliance load tester and
I plugged in two different home stereo sets to get an idea of what kind of draw they take in and it was in the range of 3-4 watts at 120V and not even giving me a reading on the amp/h scale. There is no way your I-Pod speaker system would draw 96 watts at 120V. The information you may have gotten is that the speakers are rated for that wattage but the voltage reaching your speakers is very low. I would estimate the draw of your radio at a maximum of 6W at 120V or approximately 60W at 12V. With inverter inneficiency I would estimate you would do rather nicely with an inverter rated at 100W. As long as you are getting an inverter I would recommend you get a 400W as the difference in price will not be significant and you may use it for other applications like lighting your X-Mas lights while listening to music. VECTOR makes a 400W that sells for about $35. Beyond this wattage the price climbs and they require a hard wired installation which can be rather costly in itself. You can still use a 12V lighter type connector making the unit fully portable. (Manufacturers recommendation is that if you use any inverter with a load exceeding 150W that you hard wire it, but I don't think you will come close). This small inverters can be quite noisy as they require a fan for cooling so you may want to extend your 120V circuit by using an extension cord and placing your radio away from the source. The power consumption on your 12V batteries should be minimal and in the order of .75 amp/h providing many hours of enjoyment before you hit the 50% discharge capacity of your batteries.
I plugged in two different home stereo sets to get an idea of what kind of draw they take in and it was in the range of 3-4 watts at 120V and not even giving me a reading on the amp/h scale. There is no way your I-Pod speaker system would draw 96 watts at 120V. The information you may have gotten is that the speakers are rated for that wattage but the voltage reaching your speakers is very low. I would estimate the draw of your radio at a maximum of 6W at 120V or approximately 60W at 12V. With inverter inneficiency I would estimate you would do rather nicely with an inverter rated at 100W. As long as you are getting an inverter I would recommend you get a 400W as the difference in price will not be significant and you may use it for other applications like lighting your X-Mas lights while listening to music. VECTOR makes a 400W that sells for about $35. Beyond this wattage the price climbs and they require a hard wired installation which can be rather costly in itself. You can still use a 12V lighter type connector making the unit fully portable. (Manufacturers recommendation is that if you use any inverter with a load exceeding 150W that you hard wire it, but I don't think you will come close). This small inverters can be quite noisy as they require a fan for cooling so you may want to extend your 120V circuit by using an extension cord and placing your radio away from the source. The power consumption on your 12V batteries should be minimal and in the order of .75 amp/h providing many hours of enjoyment before you hit the 50% discharge capacity of your batteries.
50% discharge?
I was at batteries plus and was looking at an 80 AH battery that is a agm (?) and was told I can discharge this without hurting it at all as long as I charge it back up with an 1.5 or so charger. Is this not correct? I was thinking at 2 6v trojan but I think 230 aH is a bit excessive, 80 should be fine I think. Opions?
I was at batteries plus and was looking at an 80 AH battery that is a agm (?) and was told I can discharge this without hurting it at all as long as I charge it back up with an 1.5 or so charger. Is this not correct? I was thinking at 2 6v trojan but I think 230 aH is a bit excessive, 80 should be fine I think. Opions?
AGM
AGM batteries can take a deeper discharge and not suffer like lead acid batteries. I think an 80 AH AGM battery would be fine for your needs. (but what do I know)
AGM batteries can take a deeper discharge and not suffer like lead acid batteries. I think an 80 AH AGM battery would be fine for your needs. (but what do I know)
Consider a car amp
SweetTrade, Consider a car amp. I have a 100 watt car amp that came with my boat and a nice pair of Tannoy studio monitors. The amp is basically invisible as it is mounted to a bulkhead under the chart table. It is an extremely simple matter of hooking my ipod to it and it sounds incredibly fantastic! The ipod controls the volume and i've never had to turn it up all the way. It sounds so good that I had to help one of the guys on my dock hook up a car amp (50 watt) on his boat for his ipod. His sounds great also. Bonus is that I can hook up my XM reciever, tv, or ipod shuffle to it all on the same jack. Also think of what the moisture associated with boating will do to an expensive Bose system. You wont be as upset if an inexpensive amp gets a little corrosion inside and quits working.
SweetTrade, Consider a car amp. I have a 100 watt car amp that came with my boat and a nice pair of Tannoy studio monitors. The amp is basically invisible as it is mounted to a bulkhead under the chart table. It is an extremely simple matter of hooking my ipod to it and it sounds incredibly fantastic! The ipod controls the volume and i've never had to turn it up all the way. It sounds so good that I had to help one of the guys on my dock hook up a car amp (50 watt) on his boat for his ipod. His sounds great also. Bonus is that I can hook up my XM reciever, tv, or ipod shuffle to it all on the same jack. Also think of what the moisture associated with boating will do to an expensive Bose system. You wont be as upset if an inexpensive amp gets a little corrosion inside and quits working.
Install CAR Sound System
If you stick with high end car stereo components you can run it all from your 12v system without an inverter.
If you stick with high end car stereo components you can run it all from your 12v system without an inverter.
Thanks everyone.
I appreciate all your help. I think I am going to go with a 300 watt pure sine inverter (since the next one up i could find was 1000 with a big $$) and a 80 aH AGM battery. I was thinking about 2 6v but for my needs I think this will be fine and 300 watts should easly power the speaker and any other small thing I might want to run. Also a 1.5 charger, Although I would like a bigger one I heard this would keep my battery longer. Thanks Jeff
I appreciate all your help. I think I am going to go with a 300 watt pure sine inverter (since the next one up i could find was 1000 with a big $$) and a 80 aH AGM battery. I was thinking about 2 6v but for my needs I think this will be fine and 300 watts should easly power the speaker and any other small thing I might want to run. Also a 1.5 charger, Although I would like a bigger one I heard this would keep my battery longer. Thanks Jeff
A 1.5 amp charger will keep a charged battery . .
"floated" OK but will take forever to charge a depleted battery. I'd suggest a 5-6 amp charger that is smart enough to down-shift to float/trickle at the correct voltage. I believe those sizes are available for less than a Boat Unit.
"floated" OK but will take forever to charge a depleted battery. I'd suggest a 5-6 amp charger that is smart enough to down-shift to float/trickle at the correct voltage. I believe those sizes are available for less than a Boat Unit.
2 amp charger
I've used a 2 amp charger to recharge my batteries. It was cheap and automatically goes to float. An indicator goes from yellow to green. If does take time but if you have time why not??? Also a battery will only accept so many amps so even with a bigger charger it will only put out a max amperage for a brief period. My boat's 20 amp charger rarely indicates more than 5 amps and this quickly drops to about an amp. With the little 2 amp I just hook it up and check it a day or two later. I have three batteries on my boat. Two deep cycle and one combo deep cycle/starting. One deep cycle is not hooked to the alternator and is kept charged for anchor lights and emergency starting. It's this emergency battery that I keep charged with the 2 amp. One time having to pay $150 for a boost convinced me to keep a charged emergency battery. Oddly since I have had the emergency battery I've had no problems.
I've used a 2 amp charger to recharge my batteries. It was cheap and automatically goes to float. An indicator goes from yellow to green. If does take time but if you have time why not??? Also a battery will only accept so many amps so even with a bigger charger it will only put out a max amperage for a brief period. My boat's 20 amp charger rarely indicates more than 5 amps and this quickly drops to about an amp. With the little 2 amp I just hook it up and check it a day or two later. I have three batteries on my boat. Two deep cycle and one combo deep cycle/starting. One deep cycle is not hooked to the alternator and is kept charged for anchor lights and emergency starting. It's this emergency battery that I keep charged with the 2 amp. One time having to pay $150 for a boost convinced me to keep a charged emergency battery. Oddly since I have had the emergency battery I've had no problems.
One other option
If you are definitely going with a 120v system, take a look in Home Depot. They sell a 120v (and 12v) power supply, jump starter, inverter, air compressor, and led light gizmo for about $89. I bought one last winter since I didn't have electricity at my marina. I could get 1.5 hours of use with my big orbital sander, or enough juice to top off my battery, or just enough to vacuum the interior of my boat with a wet dry vac. It's probably strong enough to power your bose system for a few hours and still have enough charge for an unexpected jump start. So far this summer I was able to jump start 3 boats (2 with 350s in them) and inflate my fenders. My friend would also ask me to bring it with us when we would go sailing on his boat just in case he needed a jump. Manny
If you are definitely going with a 120v system, take a look in Home Depot. They sell a 120v (and 12v) power supply, jump starter, inverter, air compressor, and led light gizmo for about $89. I bought one last winter since I didn't have electricity at my marina. I could get 1.5 hours of use with my big orbital sander, or enough juice to top off my battery, or just enough to vacuum the interior of my boat with a wet dry vac. It's probably strong enough to power your bose system for a few hours and still have enough charge for an unexpected jump start. So far this summer I was able to jump start 3 boats (2 with 350s in them) and inflate my fenders. My friend would also ask me to bring it with us when we would go sailing on his boat just in case he needed a jump. Manny
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