Using Unique Controlling-technique
Based on considerable practically experience a unique PID controlling-technique has been evaluated. The controller is able to maintain the desired temperature with least possible fluctuation.
3 x 0-10 V DC control signal is available for motors controlling dampers and valves for in- and outlet of air. Operating range - normally 1.5-10V.
A built-in phasecut-device controls the speed of the fans. The fanmotor can be shut off automatic when not required.
The supply of heat can be on/off controlled (heat fan). A 0-10 V control signal is available for motorshuntvalve or other variable heat source supply.
It is possible to setup the two heat outputs so that they will work in a sequence, i.e. when the 1st heat source is inadequate the next starts to supply, both working from 0-100 % supply.
The alarm-relay has potential-free switches for both on and off in case of alarm.
Alarm limits may be set for high and low temperature.
Alarm limits may be set for high and low temperature, relative to the Set Temperature
Back-up by Power Failure
The controller can be powered by 12 V DC and consequently it can continue monitoring temperature and control dampers and valves.
RS 485-interface opens up for many possibilities.
- Interface with PC could provide you with a nice survey of a number of units. General operation can also be carried out.
- By means of an optional Speech Processor inquiries and operation can be done through telephone.
Heron (abt. 100 BC)
Heron was one of the great scientist during the Greek Golden Age. His numerous descriptions of hydraulic constructions, mostly bases on the siphon-principle, have survived till time. This includes the description of a system for automatic opening and closing doors controlled be temperature. This is the oldest known description of a mechanical air-conditioning system.