Category
pH & ORP Transmitters and Controllers
Single, dual and multi-channel pH and ORP analysers for dosing control.
A pH transmitter or ORP transmitter turns an electrode's raw signal into a readable value, alarms and a dosing output, and Chemitec's Series 30, 46 and 50 scale from a single measurement point to eight simultaneous parameters. Choose by how many channels your dosing or monitoring station needs, from a single pH loop up to a multi-parameter effluent station.
3 Products · pH/Orp Transmitter & Controller
Selection guide
pH & ORP Transmitters and Controllers Guide
How a pH/ORP transmitter or controller works
The electrode generates a small millivolt signal that changes with the medium's acidity (pH) or oxidising power (ORP). The transmitter amplifies that signal, converts it to a pH or mV value using a stored calibration, and compares it against your set points to drive alarms, a proportional dosing output or a relay. On a multi-channel unit, each parameter runs its own calibration and set points, so pH, conductivity and other inputs can be logged and controlled from the same display.
How to choose a pH/ORP transmitter
- Channel count: Series 30 for one analytical sensor (pH/ORP, conductivity or a custom 4 to 20 mA input); Series 46 for one or two parameters, including pH/ORP, conductivity, dissolved oxygen, turbidity, suspended solids, chlorine or ozone; Series 50 for up to 2, 4 or 8 simultaneous measurements at one monitoring point.
- Display: Series 30 has a 128 x 128 pixel graphic display showing value, bar graph, temperature and output status; Series 46 has a three-colour backlit display in IP65 panel or wall housing; Series 50 has a 480 x 272 colour display.
- Dosing control: all three raise alarms and drive outputs for a dosing pump; Series 50 adds 4 analogue and 4 digital command outputs for larger control schemes.
- Third-party sensors: Series 30 and 50 accept a universal 4 to 20 mA input, so most transmitters with that output can connect alongside Chemitec's own digital sensors.
For the electrodes these transmitters pair with, see pH & ORP Electrodes.
FAQ
Common questions
Which pH analyser should I choose for one measurement point?
The Chemitec Series 30 suits a single measurement, such as one pH or ORP loop, with a 128 x 128 pixel graphic display showing the value, a bar graph, temperature and output status. Move up to Series 46 or 50 once you need a second parameter or more channels at the same point.
Can the pH controller drive a dosing pump automatically?
Yes. All three Chemitec series (30, 46 and 50) raise alarms and provide outputs that drive a dosing pump directly from the pH or ORP reading, so acid or alkali dosing tracks the measured value instead of running on a timer.
How many parameters can one transmitter measure at once?
It depends on the series: Series 30 handles one, Series 46 handles one or two, and Series 50 handles up to 2, 4 or 8 simultaneous measurements with a 480 x 272 colour display, 4 analogue outputs and 4 digital command outputs.
Can I connect a third-party pH sensor to these transmitters?
Series 30 and Series 50 accept a universal 4 to 20 mA input alongside Chemitec's own digital sensors, so most pH or ORP transmitters with a standard 4 to 20 mA output can be wired in without replacing your existing electrode.
What's the difference between a pH transmitter and a pH controller?
In practice the terms overlap on these units: each one both transmits the reading (display, 4 to 20 mA or Modbus output) and controls dosing (alarms, relay or analogue outputs to a pump). The choice between Series 30, 46 and 50 is really about channel count and display, not transmit versus control.
Which Chemitec series suits an effluent monitoring station?
The Series 50 suits a multi-parameter effluent station, since it logs up to 8 simultaneous measurements with 250,000 records, a colour display and both analogue and digital command outputs, covering pH alongside conductivity, turbidity, suspended solids or BOD/COD from one unit.
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