Analysers
pH Indicator / Controller / Transmitter
The Accumax pH Controller is an industrial pH indicator, controller and transmitter covering the full 0 to 14 pH range with ±0.1 pH accuracy and 0.01 pH resolution. It offers manual or automatic temperature compensation, password-protected buffer calibration at up to three points, and a 16x2 backlit LCD.
Key specifications
- Output
- RS-485 Modbus / 4-20 mA
- Protection
- IP 20 (for panel mount), IP65 (Field Mount)
- Power supply
- 85 - 300VAC 50/60Hz or 24VDC +/- 2VDC
- Process pressure
- 6 bar
Key figures transcribed from the datasheet and pending engineering sign-off. Full specifications below.
Features
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High accuracy
Precision pH measurements with ±0.1 pH accuracy.
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Wide measurement range
Measures pH from 0 to 14.
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Temperature compensation
Automatic adjustment for temperature variations; manual or automatic.
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Digital display
Large, backlit 16x2 LCD for easy readability.
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Easy, password-protected calibration
User-selectable buffer calibration up to 3 calibration points; password protection allows quick calibration while reducing downtime.
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Communication
RS485 Modbus and 4-20 mA output for SCADA system integration.
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Relay output
Two relays available for process control and alarms.
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IP65 field-mount enclosure
IP65 in the field-mount version for washdown and outdoor use; IP20 in the panel-mount version for installation inside a panel.
Technical specifications
38 values · 7 groups
These values are transcribed from the manufacturer's datasheet and are pending engineering sign-off. Confirm critical figures with Accumax before specifying.
| Measurement | |
|---|---|
| Measurement | pH / Temperature |
| pH Range | 0.00 to 14 pH |
| pH Resolution | 0.01 Digit |
| pH Accuracy | 0.10 pH |
| I/P impedance | 10^12 Ohms |
| Temp range | 0 to 160 C |
| Temperature resolution | 1 Digit |
| Temp. Accuracy | 0.5 |
| Temp Compensation | Auto / Manual |
| Temp Sensor I/P | Pt-100 RTD (2-wire connection) |
| Buffer calibration | User selectable Buffer calibration up to 3 calibration points |
| Error indication | Buffer Out of range error; Slope error / sensor error |
| Display & Interface | |
| Display | 16 * 2 LCD |
| User Interface | 4 tactile Buttons |
| Electrical | |
| Power Supply | 85 - 300VAC 50/60Hz or 24VDC +/- 2VDC |
| Relay o/p | 2 relay |
| Control set point | Two / four set points (high and low) |
| Connection | Terminal |
| Communication | |
| Output | RS-485 Modbus / 4-20 mA |
| Baud rate (selectable) | 2400, 4800, 9600, 19200, 38400 |
| Parity (selectable) | NONE, ODD, EVEN |
| Stop bit (selectable) | ONE, TWO |
| Modbus output format | Float, Integer, Long integer |
| Modbus holding registers | 40000 pH; 40002 Temperature; two set points: 40004 Low Point for Relay 1, 40006 High Point for Relay 2; four set points: 40008 Low Point 1 for Relay 1, 40010 High point 1 for Relay 1, 40012 Low Point 2 for Relay 2, 40014 High Point 2 for Relay 2 |
| 4-20 mA connection | I+ (PIN 5) and GND (PIN 7) |
| RS485 connection | D+ (PIN 3) and D- (PIN 4) |
| Mechanical | |
| Dimensions | 96x96x85 mm / 180*130*100 mm (Field Mount) |
| Type | Panel mount / field Mount |
| IP rating | IP 20 (for panel mount), IP65 (Field Mount) |
| Sensor | |
| Type | online / tank |
| Material | glass bulb with PVC/Teflon body (As per Requirement) |
| Dimensions | Length 17cm, Dia 25mm |
| Sensor Output | mV / temperature (optional) |
| Process Connection | 3/4" BSP M |
| Cable | single core 5 meter, Multicore with PT100 output (Cable length as per Requirement, up to 15 meter) |
| Pressure | 6 bar |
| General | |
| Warranty | 12 month warranty; does not cover perishable items like pH Sensors |
| Package Contents | pH controller device, pH electrode, user manual |
Sources: pH_controller_Datasheet, pH_controller_Manual
4 further specification s are listed in the datasheet but not reproduced here
These labels appear in the datasheet, but the value beside them could not be read reliably from the document. Rather than print a figure we cannot stand behind, we have left them out — ask us and we will confirm them directly.
- Operating Environment — value only partially survives the text layer; both the datasheet and the manual show the row as '50 °C' with the lower bound of the range lost, so no operating-temperature range is recorded
- Sensor temperature rating — the datasheet row reads 'Temprature | 70 C /0 | 150C (As per Requirement)'; the range bounds cannot be reconstructed from the text layer
- Temp. Accuracy value in pH_controller_Datasheet (the label is printed with an empty cell; the figure recorded above comes from pH_controller_Manual instead)
- Temperature resolution value in pH_controller_Manual (label present, cell shows only 'Digit'; the figure recorded above comes from pH_controller_Datasheet instead)
Applications
- Water treatment plants — monitoring and controlling pH in treatment processes
- Food and beverage production — ensuring product quality and safety
- Chemical manufacturing — maintaining optimal pH in processes
- Pharmaceutical manufacturing — pH monitoring in drug production and research
- Environmental monitoring — measuring pH in natural water bodies and samples
Frequently asked questions
What pH range and accuracy does the Accumax pH Controller offer?
It measures the full range from 0 to 14 pH with an accuracy of ±0.1 pH and a resolution of 0.01 pH.
Can it be integrated with a SCADA or PLC system?
Yes. It provides RS485 Modbus communication and a 4-20 mA output for SCADA system integration, plus two relay outputs for process control and alarms.
What power supply does it need?
It accepts a universal supply of 85 - 300 VAC at 50/60 Hz, and also 24 VDC.
How is the controller calibrated, and can operators change the calibration?
Calibration uses user-selectable buffers at up to three calibration points, and it is password-protected — the source notes this allows quick calibration and reduces downtime.
Does it compensate for process temperature changes?
Yes. Temperature compensation can be set to manual or automatic.
What ambient conditions can the instrument itself be installed in?
The datasheet gives an operating environment of 50 °C; the lower limit is not printed. The enclosure is IP65 in the field-mount version and IP20 in the panel-mount version.
Gallery
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