Small Conductivity Controller

Small Conductivity Controller Introduction

The model C7335 is our small case conductivity controller and is a member of our 7335 series of analytical instruments. The 7335 series are housed in 48 x 96 Din standard enclosures which are only 95mm deep, designed for mounting in panels where space is at premium. The C7335 is also available in a surface mounting enclosure.

With a large bright display, the current conductivity value on the C7335 controller is easily visible even in bright sunlight.

Despite the compact size of the small panel mount conductivity controller, the C7335 has 2 x control relays offering High / Low operation with optional delay timers. The C7335 also has an alarm relay and an industry standard isolated 4-20mA output signal, isolated into 600Ω.

The C7335 is powered via a switch mode power supply allowing a supply voltage of either 85-264 VAC 50 / 60Hz.

C7335 Conductivity Ranges

The C7335 Conductivity controller features selectable ranges for µS (micro-siemens) and mS (milli-siemens) over the following ranges:-

Temperature Compensation

Considering the importance of temperature on conductivity readings, the C7335 can work with a conductivity cell with integrated automatic temperature compensation, or with an external RTD Temperature measuring device.

The temperature compensation co-efficient of the C7335 is user selectable, allowing the user to take more control of their process. The ATC co-efficient can be selected between 0-3.5% per ºC of the measured, value against a base of either 20ºC or 25ºC.

4-20mA Output

The C7335 has an industry standard 4-20mA output which correlates to the user selectable ranges. This ensures that the 4-20mA will give an accurate output corresponding to the range, with 4mA at the lowest point, and the 20mA at the top of the selected range.

The 4-20mA output is isolated into 600Ω so that it is incredibly easy to connect to a PLC, Online Data Logger or to a digital Chart Recorder or other device.

Conductivity Cell Constants

The C7335 will work with any good quality AWE conductivity cell instruments,  including our range of dip mounting conductivity cells and insertion conductivity cell range.

Compatible cell constants for the C7335 include:-

• K=0.1
• K=1.0
• K=10.0

Control Relays

The front panel of the C7335 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 of 0-100 seconds.

One adjustable alarm relay with delay timer is fitted which may be set to operate on both a high and low measured value.

There is also a logic input on the C7335 which takes a volt free contact closure input. When activated the logic input isolates the output relays preventing them from energising. The Logic Input can be connected directly to the alarm relay if required.

C7335 Features & Benefits

The C7335 is a simple to use conductivity controller. There are 4 centrally mounted keypads on the front of the instrument allowing the most commonly used options to be easily highlighted and adjusted.

In addition there is a password locked configuration screen which allows the user to change the less frequently adjusted settings.

For routine calibration of the instrument, the Zero and Span of the instrument are easily adjustable from the main menu with a quick and easy menu driven calibration procedure.

The measuring range in µS or mS is clearly visible on the front panel of the instrument as are the current status of the set-point 1 relay and the set-point 2 relay. In addition the alarm relay status is clearly visible from the front of the instrument, as is the logic input status.

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. Installation of the 7335 series of instruments is intended to be into a control panel or in the optional surface mounting enclosure.