HOT AMP - Cooling suggestions
#1
Launching!
Thread Starter
HOT AMP - Cooling suggestions
My setup is as below.
1) These are huge images (some nearly 1.5 MB in size), dialup users beware.
2) If you link directly, they will be removed. Please link to this thread.
http://home.comcast.net/~zx1100e5/pics/100_1140.JPG amp rack 1
http://home.comcast.net/~zx1100e5/pics/100_1141.JPG amp rack 2
http://home.comcast.net/~zx1100e5/pics/100_1142.JPG amp rack 3
http://home.comcast.net/~zx1100e5/pics/100_1143.JPG amp rack 4
Previous pics http://home.comcast.net/~zx1100e5/pics/
The smaller amp is an alpine 3552.
After running a while, it gets hot.. really hot. Not enough to trip its thermal protection (I assume being a top of the line amp from 1992? it has this), but awfully hot to the touch.
I'm tossing the idea of hooking up some 120mm pc fans. Noise isn't much of an issue since its all the way in the back, and I'll never hear them over road noise anyways.
I know the remote on goes to +12 when the HU is active. But also, I believe the remote on is limited to 200-300 mA max. I was thinking of devising a small circuit using a darlington driver to power the fans directly. The IC I have in mind is a 6 or 7 channel, 500mA max/channel capable device.
Any other suggestions?
1) These are huge images (some nearly 1.5 MB in size), dialup users beware.
2) If you link directly, they will be removed. Please link to this thread.
http://home.comcast.net/~zx1100e5/pics/100_1140.JPG amp rack 1
http://home.comcast.net/~zx1100e5/pics/100_1141.JPG amp rack 2
http://home.comcast.net/~zx1100e5/pics/100_1142.JPG amp rack 3
http://home.comcast.net/~zx1100e5/pics/100_1143.JPG amp rack 4
Previous pics http://home.comcast.net/~zx1100e5/pics/
The smaller amp is an alpine 3552.
After running a while, it gets hot.. really hot. Not enough to trip its thermal protection (I assume being a top of the line amp from 1992? it has this), but awfully hot to the touch.
I'm tossing the idea of hooking up some 120mm pc fans. Noise isn't much of an issue since its all the way in the back, and I'll never hear them over road noise anyways.
I know the remote on goes to +12 when the HU is active. But also, I believe the remote on is limited to 200-300 mA max. I was thinking of devising a small circuit using a darlington driver to power the fans directly. The IC I have in mind is a 6 or 7 channel, 500mA max/channel capable device.
Any other suggestions?
#3
Launching!
Thread Starter
These standard 30A relays, what are the coil ratings? The spec from the HU is not to exceed 300mA on the remote turn on.
I wonder what the typical amp draws to be triggered on.
I wonder what the typical amp draws to be triggered on.
#4
TECH Apprentice
iTrader: (3)
Amps are supposed to get hot. They are designed to work and operate well when they heat up like that. I run two kicker 850 watt amps in my car at 3/4 gain and they get VERY hot to the touch. If they don't kick into thermal protection, then let them do what they are designed to do.
#5
Launching!
Thread Starter
Trent,
I don't entirely agree with you. Heat is a byproduct of the amplification process. Obviously the amp is quite inefficient if much power is wasted as heat. Given this amp is ~15 yrs old and uses older technology that would make sense (about being inefficient).
However, heat and solid state is not preferred. The hotter something gets, the more likely for component failure.
In addition, consider thermal wear - each time the device goes through a thermal cycle, it expands and contracts [at cool down]. Eventually the device fails because of microscopic cracks developed.
I don't entirely agree with you. Heat is a byproduct of the amplification process. Obviously the amp is quite inefficient if much power is wasted as heat. Given this amp is ~15 yrs old and uses older technology that would make sense (about being inefficient).
However, heat and solid state is not preferred. The hotter something gets, the more likely for component failure.
In addition, consider thermal wear - each time the device goes through a thermal cycle, it expands and contracts [at cool down]. Eventually the device fails because of microscopic cracks developed.
#6
10 Second Club
iTrader: (9)
Join Date: Jan 2004
Location: Daytona Beach, FL
Posts: 560
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by GPz1100
These standard 30A relays, what are the coil ratings? The spec from the HU is not to exceed 300mA on the remote turn on.
I wonder what the typical amp draws to be triggered on.
I wonder what the typical amp draws to be triggered on.
Trending Topics
#8
Launching!
Thread Starter
Redline2k: I was under the impression those bosch style relays took more mA to energize. I also do this for a living, but haven't had too much exposure to these recently.
methane: In an ideal world, 100% of the energy would go towards the sound
The 3552 uses BJT's for its output stage, not mosfets like current amps. Running in bridged mode (85 x 2) driving a pair of 4 ohm speakers (1 speaker for each channel).
The amp was in service until ~2001 when I sold the last car it was in.. Been sitting on a shelf since. Still works well today, and would like to get more years out of it.
methane: In an ideal world, 100% of the energy would go towards the sound
The 3552 uses BJT's for its output stage, not mosfets like current amps. Running in bridged mode (85 x 2) driving a pair of 4 ohm speakers (1 speaker for each channel).
The amp was in service until ~2001 when I sold the last car it was in.. Been sitting on a shelf since. Still works well today, and would like to get more years out of it.
#9
10 Second Club
iTrader: (9)
Join Date: Jan 2004
Location: Daytona Beach, FL
Posts: 560
Likes: 0
Received 0 Likes
on
0 Posts
The coil rating on the relay is 160mA at 400Ohms
Just in case you still have a doubt
I am an MECP certified installer and I have been doing it for 16 years. A bosch style relay is the best way to do what you want to do. Also if the amp is that old it may not have any thermal protection. Old Rockford Amps had no thermal protection until one of them actually caught a guys car on fire and they got sued.
Just in case you still have a doubt
I am an MECP certified installer and I have been doing it for 16 years. A bosch style relay is the best way to do what you want to do. Also if the amp is that old it may not have any thermal protection. Old Rockford Amps had no thermal protection until one of them actually caught a guys car on fire and they got sued.
#10
Launching!
Thread Starter
Originally Posted by redline2k
Assuming 12V operation, if it draws 160 mA, then the coil resistance should be ~ 75 ohms (R=V/I). If the coil is indeed rated at 400 ohms, then the current should be ~30 mA.
But, in either case, agreed, it should work without overtaxing the sourcing ability of the remote turn on from the HU.
Re thermal protection, according to the alpine tech I spoke with yesterday, it does indeed have this function.
#11
TECH Junkie
iTrader: (7)
Join Date: Aug 2004
Location: Prairie de Femme, LA
Posts: 3,809
Likes: 0
Received 0 Likes
on
0 Posts
or 64v. if you wnated fans then you could have some that are temp activated. http://www.heatsink-guide.com/conten...=control.shtml here is a way to make a temp controlled 12v fan