The model P7335 is our small case Redox controller and is a member of our series 7335 analytical instruments. The 7335 series are housed in 48 x 96 din standard enclosures which are only 95mm deep and designed for mounting in panels where space is at premium.

The P7335 Redox (ORP) millivolt / pH Controller features selectable ranges for Redox millivolts over the range of 1000 mV to +1000 mV. The user can also select whether to measure and control pH with a glass electrode, as well as pH using an Antimony electrode which may be used in solutions containing HF acid.

For pH measurement, the temperature compensation may be manually set over the range of 0-100ºC or automatically compensated for over the range of 0- 100ºC, by the use of a temperature sensor which is user selectable. A bright red LED indicates the selected mV or pH, the main readout features a 4 digit red LED display, which provides excellent visibility and provides the user with messages for setup and operation.

The front panel includes 4 keys that allow the user to access the most frequently used functions. Two programmable control relays are fitted.  The control relays can be programmed for either high or low operation and have adjustable delay timers. One adjustable alarm relay with delay timer is fitted, which may be set to operate on both a high and low measured value.

The isolated current output corresponds to the measuring range selected, either Redox in mV or the pH value, and can be selected for either 0-20 mA or 4-20 mA.

The versatility of the microprocessor accompanied by the user friendly software allows the programming of the functions; routine checks and calibration, to be easily accomplished even by untrained operators. Installation of the 7335 series of instruments is intended to be into a control panel or in the optional surface mounting enclosure.

The rear of the case is fitted with plug-in connector blocks, for ease of installation and maintenance.

Compact Redox Controller 4-20mA output for use with PLC's and Chart Recorders

The P7335 Redox Controller has an isolated current output which corresponds to the measuring range selected (either pH Control or Redox Control) and can output either a 0-20mA or a 4-20mA signal. The current output is non-expandable and is most commonly used with a PLC or Chart Recorder.

The P7685 Proportional Redox controller is available in either panel mounting or surface mounting configuration.

P7685 Proportional Redox Controller Introduction

The P7685 Redox controller is designed to provide reliable, accurate, repeatable and dependable measurement and control of the Redox value in many industrial process.

For those applications where precise control is required our model P7685 proportional Redox controller is the ideal partner featuring two proportional outputs, an expandable 4-20mA output and an alarm relay with delay timer.

The P7685 has a 16 character alphanumeric LCD that displays the measured parameter and provides information about the state of the control and alarm relays. Also accessible is an indication of the operating condition of the sensor.

The versatility of the microprocessor accompanied by the user-friendly software allows the programming of the functions, routine checks and calibration to easily be accomplished even by untrained operators. The model P7685 proportional redox controller is a microprocessor panel mounting Redox (mV) / pH / Temperature instrument.

The controller is designed for control panel mounting in a 92 x 92mm din standard cutout and is also available as a surface mounting instrument.

The key design of the P7685 instrument is the precision measurement of a solutions Redox value or pH value and then to proportionally control equipment relative to this value.

The measuring discipline is user selectable between a redox electrode, pH electrode or Antimony pH Probes. The temperature input provides both a selectable temperature indication and auto temperature compensation of the pH range.

The P7685 proportional redox controller measures across the ±1000mV for the Redox range and across the full 0.00-14.00 pH scale. The temperature is measured and compensated from -10ºC to +110ºC for stand alone or pH measurements.

For Redox measurement we recommend pairing the P7685 with an AWE Platinum band Redox Probe or another precision Redox probe.

The unit operates from a power supply of either 110 VAC or 230 VAC 50/60Hz.

Redox Controller Proportional Control Relays, PFM, PWM, or On/Off Control and Alarm Relay.

The model P7685 proportional Redox controller features two control relays which can be programmed for either On/Off control, PFM control to proportionally control electronic metering pumps or PWM to time proportionally control solenoid valves or small pumps.

The P7685 is also fitted with an adjustable alarm relay with delay timer. This can operate on both a high and low measured value.

The proportional control relays offer PFM (pulse frequency modulation) output for proportional control of our electronic dosing pumps. The P7685 has adjustable set points and is proportional band selectable.

As a proportional Redox controller, the P7685 is excellent for maintaining a redox value during process critical operations. For instance when the requirement is pre-treatment of water prior to passing through a Reverse Osmosis membrane to remove any residual chlorine, a 100mV setpoint is often used and then a reducing agent such or as Sodium Metabisulfite (or another sulphur dioxide salt) is dosed. Using the proportional control relays the 100mV can be accurately maintained and wastage is significantly reduced by not over-feeding the reducing agent.

Redox controller with expandable 4-20mA for proportional control

The P7685 Redox Controller has an expandable 4-20mA current output, which can be set to be proportional to the measured value.

The industry standard 4-20mA is both powered and isolated to 600Ω and works with compatible dosing pumps as well as PLC's, Data-loggers, and other associated items.

The 4-20mA is expandable across the full redox measured range (and pH if the instrument is configured for this parameter) and can be expanded across a set range, for example a value of 20mA at 100mV and a value of 4mA at 300mV. In this example a figure of 200mV would have a current signal value of 12mA.

The P7685 proportional Redox controllers are normally available for ex-stock deliveries.

The P7635 Redox Controller is available in either surface mounting or panel mounting configuration, with either a P7635 panel mounting or P7635-W in surface mount enclosure.

P7635 Redox Controller Introduction

The P7635 Redox Controller is a panel mounting Redox controller with a large bright red LED digital display in a DIN spec housing 96 x 96mm and is designed for the DN 47300 standard. This instrument also has a very short case length of only 95 mm allowing the controller to be mounted into compact sized control panels, saving on both space and cost.

The easy to use P7635 Redox Controller has 8 buttons located on the front, for easy access to the setup, configuration and calibration areas of the software. This allows the instrument to be easily setup and configured and makes periodic calibration a breeze with the dedicated Zero and Sensitivity calibration buttons.

To ease the installation of the P7635 Redox Controller the instrument is fitted with a switch mode power supply suitable for a supply voltage of 86-264 VAC.

Redox or pH measurement and control

The P7635 can be selected for use with Redox probes or pH probes. The range of the instrument is from -1000mV to +1000mV for the measurement of Redox (ORP). For the measurement of pH, this is across the full 0-14.00 pH scale. When measuring pH the P7335 has temperature compensation which may be manually set, over the range of 0-100ºC or automatically compensated for over the 0-100ºC. The Automatic Temperature Compensation is through the use of either temperature sensor, which can be mounted inside the pH electode.

When measuring or controlling the Redox value we strongly recommend pairing the P7335 Redox controller with an AWE Redox electrode or another good quality electrode.

Redox Controller with On/Off Control Relays and Alarm Relays

The P7635 is fitted with two programmable On/Off control relays. These can be programmed for either high or low operation and have adjustable delay timers. The on/off control relays are SPST 5 amp non inductive. Within the instrument, a mV (Redox / ORP) value can be assigned as a setpoint (such as a value of 500mV). When the Redox value is below this point, a control relay will switch, allowing a dosing pump to activate or a normally closed solenoid valve to open.

In addition to the On/Off control relays, the P7635 includes an SPDT 5 amp non-inductive alarm relay with adjustable delay timer. This can be set to operate on both a high and low measured value. The alarm relay is often used to control an audible alarm and/or control beacon.

4-20mA output for use with PLC's and Chart Recorders

The P7635 pH Controller has an isolated current output which corresponds to the measuring range selected (either pH Control or Redox Control) and can output either a 0-20mA or a 4-20mA signal. The current output is non-expandable and is often used with a PLC or Chart Recorder.

Easy to use Redox Controller with 2 setpoints

The Model R3647-W Redox Controller is designed to be as easy to use, as possible.

When paired with a good quality Redox Probe the R3647 will display precision redox measurements in mV (millivolts). With the use of the two set point values and corresponding On / Off control relays, the redox value of the measured process can be controlled using a wide array of control equipment.

The setup and calibration of the R3647 Redox Controller has been designed to be as simple as possible and to fit into a small case. For system integrators we offer a Din-rail mounting specification, measuring just 105mm wide x 100mm high x 58mm deep. In the surface mounting enclosure the unit measures 135mm wide x 170mm high and 115mm deep.

The R3647-W is an easy to use Redox controller, has a large easy to read LCD display giving good visibility of the current mV value, to an operator.

When in surface mounting configuration, the Redox controller has a clear door for easy access to the simple to use controls, allowing the operator to calibrate the instrument or set the two set points from the front panel.

The 2 setpoints can be adjusted using the front mounted potentiometers and allow for the On / Off control relays to be set for high or low level operation. The easy to use Redox controller is able to work with any probes from our Redox Electrode range or any other high quality Redox Electrode.

The R3647-W Redox controller works across the 0-1000mV range and is designed to work with a 115 VAC or 230 VAC supply.

R3647-W easy to use Redox controller with 2 On / Off control relays

The model R3647-W easy to use Redox controller is fitted with two On / Off control relays, each with an adjustable time delay of up to 40 seconds before the relay operates. The operation of the model P3647-W Redox Controllers relays maybe selected for high or low, by two DIL switches, one for each relay. This enables the relay functions to be either High - High, High - Low or Low – Low.

When the setpoint is configured for use under low operation, ie. when the monitored Redox value is lower than the set-point value, the LED is lit and the corresponding relay is activated. If the relay has the delay function activated then the timer will be called until the relay is activated.

For use under high operation, ie. when the monitored Redox value is higher than the setpoint, the LED is lit and the corresponding relay is activated. Again, if a delay has been assigned to the relay then the relay will wait until this delay has expired before activating.

As the R3647-W is an easy to use Redox Controller with excellent control options. It makes an excellent choice as a cost effective Redox Controller for many processes including:- biocide dosing, scrubber control, effluent treatment and water treatment plants.

R3647-W easy to use Redox controller with 4-20mA output

The R3647-W easy to use Redox Controller has an industry standard 4-20mA output isolated to 500Ω. This 4-20mA output can be used with a variety of control equipment such as PLC's and chart recorders. The 4-20mA output in this instrument is non-expandable meaning that the current output is not suitable for use with proportional control dosing pumps.