CEMTROL NT: Microprocessor controller with max. 4 measuring inputs - Programming and adjusting with clear Graphic display: 134 x 40 mm (B x H); 240 x 64 points background lighting: LED yellow/green Power supply: 230/115V / 50 Hz (OPTION: 24V / 50 Hz) Power input: 18 W; Load of relays: 230 V / 50 Hz, 3 A; Housing size: 326 x 237 x 80 mm (BxHxT) for wall mounting; Protection: IP 65 with closed connections MEASURING INPUTS (according to models): - 4 inputs: free chlorine or pH or REDOX or 0/4…20 mA or feedback from servomotor - 2 inputs: 0/4…20 mA or temperature DIGITAL INPUTS (according to models): - Pre-alarm metering pump 1 - Alarm metering pump 1 - Pre-alarm metering pump 2 - Alarm metering pump 2 - Filter rinsing - Controller release: shut-off 'with' alarm; shut-off 'without' alarm CONTROLLER ACTION: P,PI, PD, PID; constant value control; 2-side control (pH value), pH-increase or pH-decrease CONTROLLER OUTPUT (according to models): - Relays: ON/OFF; pulse frequency 10…100 pulses/min; pulse length 10…120 seconds; 3-point step with feedback potentiometer 1…10 kOhm - Continuous: 0/4…20 mA, max. load 500 Ohm (not potential free) ALARM (relay output as potential-free changer): - Measured value alarm: min. and max. value freely adjustable, relay output for input 1-3 as collective alarm, time delay adjustable: max. 60 min. - Security shut-off (Y-Alarm) to avoid an over-dosing; time delay adjustable: max. 120 min. 4 CURRENCY OUTPUTS (according to model): 0/4…20 mA for measured value transmission; spreading possible, max. load 500 Ohm (not potential free) COMPUTER INTERFACE: RS 232 (OPTIONAL: RS 485 and CAN-Bus module)