A universal power supply allows a single connection to any supply between 80 to 264v, AC or DC. An option for low voltage operation between 18-36v AC or DC is also available. Adjustable temperature compensator selection of Pt100 or Pt1000 allows the instrument to be used with any LTH Electrodeless conductivity sensor.
The large backlit multi-function display guides the operator effortlessly through the structured programming procedure, reducing the need to refer
to the handbook.
An initial configuration has been pre-programmed into the MED53,
minimising the number of parameters that will actually need to be changed
for most users. The MED53 has been designed with two levels of programme complexity to cater for both novice and experienced instrument operators.
In the Basic set-up mode, only a few settings are required to configure and
run the instrument. These are the sensor type (or cell constant), display
(operating) range, set point modes and values, temperature compensation and current output range (as required).
In the Advanced set-up mode, all the options and functions, which you would normally associate with a high-end, multi-range conductivity controller, together with some new innovative options, can be configured.
On-line HELP facilities consist of a series of text error messages which
are displayed when programming is incorrect, or if a sensor is not reading a sensible value for the instrument set-up.
A further enhancement is multi-level security, where day to day operator
access can be limited to viewing data and settings only, while allowing full
access to the instrument programmer.
Configuration data can be saved in one of two independent back-up
locations, which can be used for fast reconfiguration, emergency restoration of settings, recovery after tampering by unauthorised operators, etc.
Up to 3 relay outputs offer on/off control with variable hysteresis and time delays if required. A dose alarm timer can be used to prevent overdosing under fault conditions. Should the dose relay be energised for longer than a preset time then the timer will operate and prevent further dosing.
New features include time and pulse proportional relay operation, which can be used in applications where overshoot or undershoot have been a problem, or to directly drive a diaphragm pump where previously a separate drive module was necessary.
A 4th relay can be programmed to energise on a variety of different functions including errors, instrument status, eg off-line or calibrate mode, or if a dose alarm time has been exceeded.
Up to 2 industry standard, isolated outputs provide retransmission of the measurement as 0/4-20 mA signals and can be configured as conductivity, resistivity or temperature. These are also expandable & can be offset anywhere in the chosen measurement range.
Both measurement inputs and current outputs can be individually calibrated from the front panel. For applications requiring accurate measurements it is possible to calibrate the instrument and sensor to either a standard solution or a titrated solution concentration. An off-line facility allows the instrument to be adjusted without disturbing external processes.
Automatic temperature compensation can be applied to the measurement using an adjustable linear slope. In the solution concentration mode the correct solution slope is automatically set by the instrument. For applications where temperature compensation isnot required it can be switched out. Alternatively a manual temperature can be entered, if required