Working principle of medium frequency melting furnace are: three-phase bridge type all control the ac rectifier for dc rectifier circuit, after the flat wave reactor, became a constant dc current source, then through single phase inverter bridge, the dc current inverter with a certain frequency (generally between 1000 and 8000 hz) of single-phase medium frequency current. Load is composed of induction coil and compensation capacitor, connected in parallel resonant circuit. In general, can put the failure according to the failure phenomenon of intermediate frequency power supply is divided into completely unable to not work properly after starting and starting two kinds big. As a general principle, when fault occurs, should be in the case of power cuts a comprehensive inspection of the whole system, it includes the following aspects:
(a) power: use a multimeter to measure the main circuit switch (contact) whether there is electricity, and control the fuse behind this would rule out the possibility of these element circuit.
(2) of medium frequency melting furnace: rectifier rectifier adopts three-phase fully-controlled bridge rectifier circuit, which includes six quick fuse, six thyristor, six pulse transformer and a fly-wheel diode. On quick fuse has a red indicator, indicator when normal shrinkage in the shell, when burning of fuse break it will pop up, some of the fast fuse indicator is tight, when the fuse to burn, it get stuck inside, so, to be reliable, can use a multimeter discontinuity measure of fuse, to determine whether it burn out.
没有评论:
发表评论