Flowserve LRR1-40 TDS Control Unit - Manual (Page 8)

8
Explanatory Notes
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Description
As the boiler water evaporates, the concentration of non-volatile dissolved solids (TDS)
left behind in the boiler increases over time as a function of steam consumption. If the
TDS (= total dissolved solids) concentration exceeds the limit defined by the boiler
manufacturer, foaming and priming occurs as the density of the boiler water increases,
resulting in a carry-over of solids with vapour into steam lines and superheaters. As a
consequence, the operational safety is impaired and severe damage to boiler and tubes
may occur.
In addition, excess phosphate (due to phosphate treatment) or concentrated residual
hardness particles form accumulated sludge that deposits on heating surfaces and on the
bottom of the steam boiler. The insulating layer formed by these deposits can cause the
boiler metal to become overheated, resulting in a dangerous situation since the metal is
now subjected to design pressure at an elevated temperature.
The TDS control unit LRR 1-40 in conjunction with the conductivity electrode LRG 16- 40
and the operating & display unit type URB or SPECTOR
control ensure efficient boiler
blowdown.
The quality of the boiler water is monitored with the aid of:
■ Conductivity control / limitation,
■ Continuous boiler blowdown control,
■ Automatic intermittent blowdown control.
The TDS controller LRR 1-40 can be used in combination with the conductivity electrode
LRG 16 -40 and an operating & display unit type URB or SPECTOR
control for TDS
control (conductivity limitation) and continuous boiler blowdown in steam boilers and
(pressurised) hot-water plants.
The data exchange between the control unit LRR 1-40, the conductivity electrode
LRG 16 -40 and the operating device as well as further equipment is effected via CAN bus
according to ISO 11898, using the CANopen protocol.