CEMTROL-Pool Microprocessor-controlled measurement and control system: Basic housing: for wall and switchboard mounting, fitted with 4 channels to accommodate various measuring modules: - Channels1 + 2 for control functions. - Channels 3 for measuring amplifier only, suitable for pH value temperature compensation All signal inputs are physically separated. Controller action: P, PI, PID Controller output: voltage-free relay output, 3 A at 250 V / 50 Hz. - Pulse duration-modulated. - Pulse frequency-modulated. Alarm: relay output for channels 1 + 2 as collective alarm max. and min. value freely adjustable, time delay selectable, max. 60 min., max. load 3 A at 250 V / 50 Hz. Current output for measured value transmission: 0/4...20 mA freely selectable for each slot, spreading of measuring range adjustable, 10 % minimum of the measuring range with any starting point. Display:1 off 13 mm LC display, 1 off 2-line, 16-digit, alphanumerical display, 5 mm digit height. Computer interface: RS 232 standard, RS 485 optional Voltage supply: 115/230 V, 50...60 Hz switchable, IP 65