The Atlantic has 4 relays, a 4-20 mA output and a 4-20 mA compensation input. The Atlantic incorporates 8 alarm set points and 8 timers that can be logically linked to obtain a multitude of useful functions.
Mg/l (ppm), % saturation and °C or O2% by volume and °C
Atlantic has a barometric pressure sensor, and the probe incorporates a temperature sensor. This gives correct values of dissolved oxygen in both mg/l and % saturation. If you measure in air your % volume measurement will also be correct. And, of course, you don’t need a separate temperature measurement.
Atlantic has four relay outputs and 8 set points. There will always be at least one relay output that can be used to give alarm if the oxygen level goes too low or the temperature too high. And since Atlantic measures both parameters and has logical linking you only need to use one relay.
Atlantic has 8 timers that can be used for a number of purposes. For example, alarm can be delayed so that only a sustained fault results in alarm being given.
If the process fluid or water you measure in contains a constant concentration of salt or other dissolved solids you can set a constant compensation factor in Atlantic. If the salinity varies you can connect a 4-20 mA signal corresponding to the salinity and Atlantic will vary the compensation automatically.
When measuring in a closed process a 4-20 mA process pressure signal can be connected to Atlantic. This pressure signal can then be used to compensate for pressure changes so that correct measurements are obtained. This is most useful when measuring % volume oxygen in gas.
Calibration with Atlantic is easy. Just wipe the membrane, place the probe in the air and start the process. The probe, as with all such probes, should be in temperature equilibrium with the air. Atlantic issues instructions in the display and will warn you if conditions are too unsteady to obtain a good calibration. The probe is designed to have the longest possible calibration intervals.
The Atlantic is ideal for monitoring air in rooms where other gases, for example nitrogen, are used. The Air Alarm probe holder is designed for this use.
Some gases contain large concentrations of compounds that would pollute the probe if measurement was continuous. The timers and relays in Atlantic can control a magnetic valve so that the “poisonous” gas is only fed to the probe at intervals. The output signal is “frozen” between measurements.
The probe is a simple apparatus and does not need ATEX approval. In fact, you cannot obtain approval for something that doesn’t need it. There is, however, a limit to the non-conducting area that can be placed in classified areas, so you order the metal-clad EX version of the probe and place two approved barriers between the probe and the transmitter.
The OxyGuard Probe Cleaner uses compressed air, and has proved very effective. A timer and relay in Atlantic can control the compressed air, whilst a second timer “freezes” the output when cleaning.
If you measure in biologically active water membrane fouling can change the probe sensitivity. The OxyGuard Anti-Fouling Cap reduces such fouling significantly.
Measurement principle: Oxygen: Galvanic oxygen partial pressure cell, self polarizing, self
temperature compensating. Temperature: Precision NTC
Dimensions: Diameter = 58 mm, length = 59 mm.
Weight: Probe alone 0.2 kg. Probe with 7m cable 0.5 kg.
Connections: Cable, 4 lead, standard cable length = 7 m.
Measurement range: DO 0-200% sat, 0-20 mg/l, O2 vol. 0-25%, other on request. Temp. from – 5°C.
Accuracy: Depends on calibration and conditions. Typically better than +/-1% of value.
Output stability: In air at constant temperature stable to within +/- 1% over 1 year.
Accuracy, temperature: +/- 0.3°C.
Operating conditions: 0 to 40°C, pressure to 2 bar. Higher on request. Storage temp.: -5 to +60°C.
Construction: ABS enclosure with display, indicators, pushbuttons and alarm buzzer.
Dimensions & weight: b x h x d: 213 x 185 x 95 mm, 1.2 kg.
Supply & consumption: 230 VAC, 115 VAC +/-10% or 9 to 36VDC. 10 W. Specify when ordering.
Operating conditions: -10 to +50°C. Max. 90% humidity non-condensing. Enclosure IP65.
Storage conditions: -10 to +60°. Max. 90% humidity non-condensing.
Probe inputs: mV for oxygen, NTC for temperature. Scaleable. Choice of units.
Probe input units: Oxygen: mg/l, PPM, % Sat, % Vol, mbar O2. Temperature: °C or °F.
Compensation input: 4-20 mA. Scalable. Max voltage drop 5V at 20 mA. Can compensate for salinity, pressure, temperature or NTC temperature. Can be used for separate 0-20 or 4-20 mA measurement signal input with units mg/l, PPM, % Sat, % Vol, °C, °F, mmHg, inHg, mbar O2, PPT, pH.
Analogue output: 4-20 mA. Max. load 820 ohm (total). User selectable range & parameter. Fully galvanically isolated from all inputs.
Display: Graphical LCD with backlight. Max 4 figures, 2 decimals, 13 mm height.
Conversion accuracy: To display and analogue output < +/- 0.1%. Non-linearity and repeatability typically < +/- 0.1% of actual value.
Relay outputs: 4, with potential free changeover (SPDT) contacts. Selectable mode (direct or inverted), and linking to parameter or logical argument. Max load 200VA or 1A AC, recommended max 24 VAC (abs. max 250 VAC). 2A at 24 VDC.
Logical functions: Direct, inverted, multiply. With “and” and “not and” linking.
Alarms: 8, variable hysteresis about set point. Selectable parameter, values & linking.
Timers: 8, from 1 second to 9999999 seconds (approx. 115 days). Selectable period, duty cycle and offset. Can activate or be activated by alarm. Can freeze the output. Can activate relays. Can be reset from front panel.