Gestra LRS1-7

Description The conductivity switch LRS 1-7 in conjunction with the conductivity electrode LRG 16-9 constitutes a conductivity monitoring and control system. The electrical conductvity of n Condensate, n Boiler feedwater, n Cooling and cleaning water, n Boiler water is monitored. In steam boiler plants the conductivity monitoring & control system is used as limit switch and continuous blowdown controller.

Technical Data Type approval TÜV.WÜL.xx-014 Supply voltage 230 V, +10/–15 %, 50-60 Hz 115 V, +10/–15 %, 50-60 Hz (option) Input 1 Input for conductivity electrode LRG 16-9 Output 3 volt-free relay contacts, max. contact rating for switching voltages 115 V AC and 230 V AC: resistive/inductive 4 A. Provide contactor with interference suppressor (RC combination). Contact material: AgNi 0,15. 1 Current output 4-20 mA as actual value output, max. load 500 ? Measuring range 0.5 to 10000 µS/cm at 25 °C or 0.25 to 5000 ppm at 25 °C.

Setpoint adjustable between 0.5 and 9999 ?S/cm or 0.25 to 5000 ppm MAX limit adjustable between 0.5 and 9999 ?S/cm or 0.25 to 5000 ppm Correction factor adjustable between 0.05 and 5,000, adjustable in increments of 0.001 Temperature coeffizient Tk 0.0 – 3.0 % per °C, adjustable in increments of 0.1 Actual value output 4 mA corresponds to 0.5 ?S/cm 20 mA corresponds to 10, 200, 500, 1000, 6000, 9999 ?S/cm or 5, 100, 250, 500, 3000, 5000 ppm, final values adjustable Purging interval (continuous blowdown valve is forced to open) adjustable between 1 h and 24 h in increments of 1 h. Duration of purging adjustable between 1 min. and 6 min. in increments of 1 min. Switching hysteresis Controller output: – 10 % of the adjusted setpoint W, Limit MAX: – 3 % of the adjusted MAX limit Indicators and adjustors 1 four-digit, seven-segment indicator, red, for indicating the actual value / setpoint and for status and error messages 2 amber LEDs for indicating actual value (X) / setpoint (W) 1 red LED for indicating MAX limit 2 green LEDs for indicating valve OPEN / CLOSED 4 pushbuttons for value and parameter settings