Soft start with thermal protection

Description:
The linear power supplies normally used in Audio Power amplifiers draw a very large but brief current when they are first turned on. This large current can eventually damage the bridge rectifier and filter capacitors as well as produce a 'thump' in the speaker.

This soft start circuit can be installed in the mains supply to an Audio Power Amplifier to address this problem. It will limit the initial current flow by using four robust NTC thermistors in series with the mains supply. During the turn-on period when the mains current flows through these thermistors they may heat up - this is normal and not an indication of any problems with the circuit.

Features
Triggered by a momentary switch . Any of our momentary power switches can be used with this board.

The circuit states are indicated by a bi-color led . Standby-RED ; active- Green. The LED output from this board can also be used to turn on the LED inside the LED ring type power switches. In such an installation the Active state of the circuit is indicated by the Button's LED ring and the standby state is indicated by another LED mounted on the Front Panel of the amplifier.

This board Also features a thermal protection System that gets triggered as soon as the internal temperature of the amplifier(sensed by thermal sensors mounted on the heat-sinks) reaches beyond 75 degress. As soon as this happens the trigger circuit disconnects the mains power to the Transformer . The power to the transformer can only be restored when the temperature falls below 75 degree. This Thermal protection system is a must for Class-A amplifiers and other higher rating power amplifiers.

This Circuit is absolutely free From any kind of false triggering and malfuctioning associated with several Fake Boards sold in the market.This is an exclusive design Direct From XD with a flawless operation and high quality components.

PCB Type : FR4 grade glass-reinforced epoxy board with electroless nickel plating and high grade black soldermasking.
PCB copper foil is 2 oz
PCB dimensions are 77.5MM x 92MM
Weight is 165g
Relay rated current is 30A
Rated power 1000watts

Whats Included:

Main Soft Start Board X 1
Insulated Female disconnects x 4
Themal sensors 75 Degrees X 2
Connection Cable for themal Sensors X 2
Mounting Studs and screws X 4EA
Bi colour LED x 1
LED and Switch Connecting Cable X 1