Universal Power Supply Module
This module has only three leading wires and can be connected to the original machine’s circuit in the simplest way the protective functions it has include the protections against over-voltage, over-current, short –circuit and erroneous connection of leading wires. It can be installed so conveniently and quickly that use of just two wires (the black and red wires) of this module can achieve this purpose for most machines extremely strong loading capacity and more stable and reliable usage can bring great convenience to daily maintenance and application of this product. It not only can be used to maintain and substitute various large-size color TV’s switch power supply circuit, but also is applicable for various large –size color TV’s. Moreover, it can be used in the switch power supplies of VCD, DVD, satellite receiver, etc. Now the case of color TV is used to describe its usage.
- Dismantle the switching tube or thick-film block of original power supply, and fix this module solidly on the original radiating rib;
- Connect the red wire to the original switching tube’s welding point at pole C (field effect transistor is at pole D) or to the corresponding power tube’s welding point at pole C inside the thick – film ;
- Connect the black wire to the original switching tube’s welding at pole E (field effect transistor is at pole S) or to the corresponding power tube’s welding point at pole E (black wire in parallel power supply circuit can be directly connected to hot ground (not isolated from municipal power grid).
- Cut off the line load and connect to it a 100W bulb and turn on the machine. Then regulated the module’s self – contained potential device to make the output voltage meet the required value. Output voltages of other windings can meet the requirements automatically. (When leaving factory, the module has already had its output voltage regulated to the lowest value. For application on different, products, the lowest output voltage are different, for example the lowest output for TVs ranges from 30V to 90V and the lowest output for video players is about 2 – 5V). During debugging, the voltage and potential device must be regulated by plastic handled small screwdriver;
- The blue wire is for remote – controlled switch – off. Conduction to hot ground can switch off the output. The machine that adopts light – coupled switch – off is connected to light – coupled pole C, light – coupled pole E is connected to hot ground and other connection wires are all cut off from light – coupled pole C. If there are voltage – stabilizing components on the sides of light coupling, the components should be dismantled; however the control components for switch – off should be retained, (For those machines that have two light coupling. C and E of the two light coupling should be parallelized for operation); for the series power supplies and other components connected to pole C should all be cut off;
- The blue wire is also used for precise voltage regulation. The problem of Images changing with sounds that might happen after module is loaded can be solved by restoring the original machines voltage – stabilizing components and by regulating and controlling the blue wire through light coupling In this way the purpose of precise voltage regulation can be achieved for utilizing the original machines voltage – stabilizing circuit, output voltage of this module must be regulated up by about 20V through dummy load; then the original machines voltage – stabilizing components should be switched on At this time, the output voltage can be lowered to the required value due to being subject to the original voltage – stabilizing control, and therefore, the effect of voltage – stabilizing of the module can be same as that of the original machine Failure to lower or abnormal lowering of the output voltages of the machines. That are connected to the original machines voltage – stabilizing circuit can indicate problems of the original voltage – stabilizing circuit.
- If disturbances and noise occur after installation, please remove other components that are connected to pole C of the original switching tube and attach the absorption circuit that is composed of resistance R1 (33 Ω – 56 Ω / 3W – 5W) and capacitance C1 (470 P – 1500 P / 1KV – 2KV) to switch transformers two primary terminals (Please refer to figure 1.) For whistling sounds occurring to series power supply please dismantle the capacitance parallelized with the original fly – wheel diode; if whistling sounds continue please dismantle all the capacitance that are connected to the switching tube’s pole C.
- For the phenomena of failure to start up abnormal voltage and automatic protection, please check whether the primary and secondary commutation diodes, filter capacitor and corresponding loads are in short circuit, If blue wire exist, it should be cut off first to ascertain whether the failure to start up is caused by actions of the remote – controlled switch – off circuit or by damage to this circuit. For sense power supply whether the fly – wheel diode is in short circuit or open circuit should also be ascertained;
- For power supply to the voltage reduced color TV where thick – film block (for example, STR6709) is adopted, the principal voltage can be reduced tremendously after switch – off, and can be then supplied to CPU’s operating voltage through relevant circuits, Thus, when this module is applied under this condition, a 5 K adjustable resistance needs to be connected to the blue wire in the series manner, and this resistance should be regulated to ensure that output principle voltage can range from 50V to 70V when the machine is switched off (referring to figure 3.) The absorption circuit in figure 3 is relatively applicable for voltage – reduced machines and among them, the resistance R1 is 33 Ω – 56 Ω / 3W – 5W, the capacitance C1 is 300P – 1000P / 1KV – 2KV.
Additionally is should be narrated here that for partial machines types, their switch transformers are not compatible with this module and these might result in the failure of output voltage to meet the original machines requirements and too loud noises to use this module. Never the less, this module can be used in other products, For modules that have been used before the voltage must be regulated to the lowest, output state before installation, lest excessively high voltage might damage the components when the module is used in other products. The range of this modules output voltage is wide and it is normal when voltage is not regulated to the required values, the output voltage is not stable or whistling sounds happen.
