14
Immersion or strap-on sensors
Immersion probes mounting
Sensors must be installed on the stretch of pipe in which fluid
circulates all the time.
The rigid stem (sensing element doing the measuring) must
be inserted by at least 75mm and must face the direction of
flow.
Recommended locations: on a bend or on a straight stretch of
pipe but tilted by 45° and against the flow of fluid.
Protect them to prevent water from infiltrating (dripping gates,
condensation from pipes etc.)
Installing QAD2.. strap-on sensors
Make sure fluid is circulating in the chosen location.
Eliminate insulation and paintwork (including rust inhibitor) on
a min. 100mm length of pipe.
Sensors come with straps for pipes up to 100 mm in diameter
Placing the probes
(QAD22.../QAE21.../QAP21.../RCA...)
With pumps on outlet
with 3 ways valves / with 4 ways valves
Panel system / burner control
With pumps on return
with 3 ways valves / with 4 ways valves
Strap-on or immersion sensors?
QAD2.. strap-on sensors
Advantages
z
10 sec. time constant
z
Installed with system running (no plumbing work)
z
Installation can be changed easily if it proves incorrect.
Limits:
Suitable for pipe diameters max. 100 mm
z
Can be affected by currents of air etc.
QAE2... immersion sensors
Advantages
z
Measure "mean" fluid temperature
z
No external influence on measurement such as: currents
of air, nearby pipes etc.
Limits
z
Time constant with sheath: 20 sec.
z
Hard to change installation position if it proves incorrect.
