A Real-Time Embedded Control System for Electro-Fused Magnesia Furnace

Table 1

Inputs and outputs of the controller.

Signal type	A/D; I/O	Details
3-phase electrode currents	Analog; 3-channel input	0~20 mA
3-phase electrode voltages	Analog; 3-channel input	0~20 mA
3-way raw weight value	Analog; 3-channel input	0~20 mA
Furnace rotation speed	Analog; 1-channel input	0~20 mA
Speed value set by the manual resistor	Analog; 1-channel input	0~20 mA
4-way inverter rotation speed	Analog; 4-channel output	0~20 mA
Upper and lower limit switch of 3-phase electrode	Digital; 6-channel input	Switch signal
Loosen signal of 3-phase electrode holder	Digital; 3-channel input	Switch signal
Holding signal of 3-phase electrode holder	Digital; 3-channel input	Switch signal
High temperature of hydraulic oil	Digital; 1-channel input	Switch signal
Low temperature of hydraulic oil	Digital; 1-channel input	Switch signal
Filter clogging in hydraulic station	Digital; 1-channel input	Switch signal
High pressure of cooling water	Digital; 1-channel input	Switch signal
High temperature of cooling water	Digital; 1-channel input	Switch signal
The furnace reset in place	Digital; 1-channel input	Switch signal
Automatic control mark	Digital; 1-channel input	Switch signal
Manual control mark	Digital; 1-channel input	Switch signal
Manual control electrode lift	digital; 6-channel input	Switch signal
Exhaust button	Digital; 1-channel input	Switch signal
Electric vibrator start button	Digital; 1-channel input	Switch signal
Electric vibrator stop button	Digital; 1-channel input	Switch signal
Inverter forward/stop	Digital; 4-channel output	Switch signal
Inverter reverse/stop	Digital; 4-channel output	Switch signal
Electric feeder machine start/stop	Digital; 1-channel output	Switch signal