Im using a powersupply from a computer that puts out 12v/15Ah something.
Tought it might be powerproblem so i tested it in the car yesterday still the same problem.
The amp just went in to protectmode one day when cruising, had been playing for a few hours constantly.
What about that low power protectmode?
I have no scope.
Tought it might be powerproblem so i tested it in the car yesterday still the same problem.
The amp just went in to protectmode one day when cruising, had been playing for a few hours constantly.
What about that low power protectmode?
I have no scope.
It's low-voltage protection, not low-power protection.
The low voltage protection will engage when the voltage at the B+/ground is drawn too low. It's common for this to happen when a power supply with insufficient current capacity dips in voltage as the rail caps try to charge. When this happens, the amp will pulse on until the caps charge and the inrush current is low enough for the voltage to remain above the low-voltage threshold.
Besides normal inrush current, excessive current draw from some fault can cause the amp to draw the power supply voltage down and engage the low voltage protection.
There are, however, other protection circuits that can shut down the amp.
The low voltage protection will engage when the voltage at the B+/ground is drawn too low. It's common for this to happen when a power supply with insufficient current capacity dips in voltage as the rail caps try to charge. When this happens, the amp will pulse on until the caps charge and the inrush current is low enough for the voltage to remain above the low-voltage threshold.
Besides normal inrush current, excessive current draw from some fault can cause the amp to draw the power supply voltage down and engage the low voltage protection.
There are, however, other protection circuits that can shut down the amp.
When it tries to power up, do you see a spike of DC across the output terminals (if a speaker is connected, it would pop).
When it tries to power up, do you see a significant dip in the 12v at the B+ and ground terminals?
Schematic diagram:
http://www.bcae1.com/temp/SLA1500.pdf
When it tries to power up, do you see a significant dip in the 12v at the B+ and ground terminals?
Schematic diagram:
http://www.bcae1.com/temp/SLA1500.pdf
I know some PC power supplies doesn't like inrush current like car audio amps have.
To test the power supply of the SLA1500 you can remove the rectifiers after the transformers. Than you can measure the railvoltage without load.
But if you have protection LED on, and the idle current draw is acceptable, I assume the power supply works ok.
To test the power supply of the SLA1500 you can remove the rectifiers after the transformers. Than you can measure the railvoltage without load.
But if you have protection LED on, and the idle current draw is acceptable, I assume the power supply works ok.
Its still 12v and the protectlight still on.
Do you know where the overheating-protection ting is?
What it looks like?
Feels like something like that is the problem.
I have a voltage reading pretty much everywhere i mesaure but i dont know what the values should be, so i dont know what to do?
Do you know where the overheating-protection ting is?
What it looks like?
Feels like something like that is the problem.
I have a voltage reading pretty much everywhere i mesaure but i dont know what the values should be, so i dont know what to do?
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