Description

ACS CONTROL SYSTEM LIMIT SWITCH GWA-250-U0

The GWA – 250 limit switch is used to monitor the voltage model 0…10V / 0…20mA resp. 4 … 20mA or Pt100 temperature resistance of violation resp. Below the limit value. In addition to continuous measurement, this device allows the configuration of up to two variables without the need for additional measuring devices. The GWA – 250 version is suitable for equipment monitoring and voltage control. Water and wastewater industry for water level monitoring and pump control (e.g. 15% pump on, 95% pump off). GWAP – 250 version can be used to monitor temperature process in all industries to connect Pt100 temperature resistance. As an alternative mode of operation where the key switch for setting the limit switch is integrated in the device, the S version is available where the coding key switch can be installed separately from the device and used as a remote control. These are designed for the installation of control room doors resp. front panel.

Function:-

Measuring principle

Version GWA – 250 / GWAS – 250

The connected electrical standard signal 0…10V / 0…20mA resp. 4…20mA is compared by the evaluation circuit with the set limit value at the key coding switches in % of the nominal signal range (10V / 20mA / 16mA), with reference to the respective signal zero value (0V / 0mA bzw. 4mA).

Examples:

At standard signal 0…10V the setting 50% equals a signal voltage of 5V.

At standard signal 0…20mA the setting 50% equals a signal current of 10mA.

At standard signal 4…20mA the setting 50% equals a signal current of 8mA (50% of 16mA) + 4mA = 12mA.

The connected signal device at the input can be powered by the integrated measurand transducer supply.

Version GWAP – 250 / GWAPS – 250

The voltage drop at the connected temperature sensor Pt100 is compared by the evaluation circuit with the set limit value at

the key coding switches in % of the set temperature signal range (30K / 50K / 100K / 600K), with reference to the set signal zero value (-50°C / 0°C / +50°C).

Examples:-

At zero value –50°C and range 100K the setting 50% equals a temperature of –50°C + 50K = 0°C.

At zero value 0°C and range 600K the setting 50% equals a temperature of 0°C + 300K = 300°C.

At zero value +50°C and range 30K the setting 50% equals a temperature of +50°C + 15K = 65°C.

The connected Pt100 in 2-wire resp. 3-wire technology is supplied be an internal constant current source and is supervised for wire break or short circuit.