Description
The continuous blowdown controller LRR 1?40 used in
conjunction with the conductivity sensing electrode LRG
16?40 constitutes a conductivity (TDS) monitoring and control
system. Electrical conductivity is used to measure boiler water
TDS (= Total Dissolved Solids). The blowdown controller
features the following functions:
? Two conductivity limits with one switchpoint each: TDS
high (max) alarm and TDS low (min) alarm. The TDS
low (min) alarm can alternatively be used to control an
intermittent blowdown valve.
? Three?position control within a predefined proportional
band.
? TDS level (conductivity) monitored and maintained within
a predefined control range.
? Stand?by input.
? 24 h purging pulse for continuous boiler blowdown.
The LRR 1?40 can, by choice, be provided with an actual value
output with a standard signal of 4 ? 20 mA. The TDS data are
transferred to the controller or another system component via
a CAN data bus. The controller and the conductivity sensing
electrode use the CANopen protocol.
