Spirax Sarco BC1100 User Manual

3
IM-P403-47 AB Issue 7
BC1100
6
9
12
3
0
(2)
(3)
(1)
(4)
SP
+
-
-
46
28
0
10
+
_
Clamping screw
Set point potentiometer
and LED indicators
Coarse and
fine calibration
potentiometers
Configuration label
Amber LED
Green LED
Amber LED
Purge button
Clamping screw
2. General product information
Fig. 1
2.1 General description
The Spirax Sarco BC1100 controller is part of an integrated range of boiler house equipment,
designed for DIN rail or chassis mounting. The controller is used in conjunction with a Spirax
Sarco conductivity sensor and blowdown valve to monitor and control the concentration of total
dissolved solids (TDS) in steam boilers.
The BC1100 has a set point potentiometer, and coarse and fine calibration potentiometers on
the front panel.
A green LED indicates that the controller is operating, and that the conductivity is below the
set point.
An amber LED indicates that the conductivity is above the set point.
A purge button is provided to open the blowdown valve manually, and a second amber LED
indicates that the blowdown valve is open.
Voltage, range, and output parameters are set on installation using internal switches.
The controller can be wired to give a purge every half hour of boiler firing, every half hour
(whether the boiler has fired or not), or, for applications where the sensor is mounted in the boiler
shell, to give no purge. The duration of the purge can be set using internal switches. (See
Section 4, 'Setting up the controller').
A pulsed or continuous output to the blowdown valve may be selected. The pulsed output,
(10 seconds open, 20 seconds closed), is suitable for smaller boilers, where continuous valve
operation may cause the boiler water level to fall excessively.
As well as the relay output, the BC1100 has a 4 - 20 mA (or 0 - 20 mA) output.
The output represents the controller range and may be used for remote TDS display, as a chart
recorder input, or as an input to a computer monitoring system. Note that the -ve terminal is earthed.
If required, this output signal can be held low (4 or 0 mA) when the blowdown valve is closed. The
switch-selectable feature is useful for in-line sensor installations to prevent a slowly falling signal
being transmitted when the blowdown valve is closed and the blowdown line is cooling.

Spirax Sarco BC1100 Specifications

General

Brand	Spirax Sarco
Model	BC1100
Category	Controller
Language	English