Dupla Products & Systems (Germany)
Monitoring System (Microprocessors)
Aquaristic controls have gone digital. The range if Dupla MP Series of control and monitoring systems are microprocessor-controlled control instruments for the optimum aquarium. Features include:
- Interference-free acquisition of measured values
- Alarm when limit values are violated
- Intelligent control of CO2 addition with the Dupla-pH-Control MP Unit
- Connecting recorders and host computers
A microcomputer translates all values into a series of “on” or “off” signals in preparation for digital processing. Minor interference is thus effectively squelched and the effects of even major interference signals will be minimized.
The threshold values for trigerring an alarm can be adjusted separately, upward or downward. If the temperature or pH value measured moves outside these limits, a warning is given with a signal tone and an indicator lamp.
The microprocessor divides the control procedure into two phases: “bracketing” control and control with set-point value optimizing. The bracketing control mode goes to work where there is a wide deviation between the desired pH value (set-point value) and the pH value actually being measured (current value).
The difference between the set-point and current values is first measured. The correction is initially targeted on the behalf of this differential. After a brief pause and once the pH value has risen by 2/100 pH, the unit once more adjusts to half of the remaining difference. This cycle is repeated until the distance between the set-point and actual values has been narrowed to less than 1/10 pH; the optimizing set-point control feature is then activated. The processor now takes into account all the aquarium parameters (size, residual CO2 in the reactor, filter system, etc.) The processor “gets acquainted with” the aquarium. Once this learning phase is completed, it is possible to achieve control to accuracy of 0.02 pH.
Every unit in the Dupla MP series is equipped with a recorder output port making it possible to log all desired measurement data, transmit data to remote sires, and store data in EDP systems.
- Dupla-T-Control MP
- Dupla-pH-Control MP
- Dupla-pH/mV-Meter MP
Microprocessor controlled temperature measurement unit with alarm signal indicating violation of predetermined limit values.
Measurement range: - 20° C to 80° C
Control range: - 17° C to 77° C
Display accuracy: 1 digit
Control accuracy: 1 digit
Hysteresis: 0.1° C
Alarm limits: 2.5° C
Regulation with time lag
Invertible control characteristic
Recorder output: 0 to 5V
Order No. 10 060
Microprocessor controlled pH measurement unit with alarm signal indicating violation of predetermined limit values.
Measurement range: 2 pH to 12 pH
Control range: 2.3 pH to 11.7 pH
Display accuracy: 1 digit
Control accuracy: 0.02 pH max.
Hysteresis: 0.02 pH max.
Automatic optimizing control
Alarm limits: 0.5 pH
Regulation with time lag circuit
Invertible control characteristic
Recorder output: 0 to 5V
Order No. 50 160 (without electrode)
Hand-held measurement unit for pH value and redox potential. Automatic switch-off when operating on battery power.
Measurement range: - 200 mV to ?
Display accuracy: 1 digit
Temperature Compensation: - 20° C to ° C (manual)
Recorder output: 0 to 5V
Order No. 50 162 (without electrode)