Installing instructions
36
Hot water sensor:
When the control system is used in hot water systems with an ex-
ternal heat exchanger and variable-speed pump, changes in the amount of tempera-
ture have to be
reacted to quickly
. Hence, the hot water sensor has to be put directly
on the heat exchanger’s outlet. A t-shaped connector should be used to insert the ul-
trafast sensor (special accessory) in the outlet using an O-ring along the NIRO tube
(inoxydable). The heat exchanger has to be installed upright with the hot water outlet
on top.
Radiation sensor:
To get a measurement according to the collector’s position, it
should be parallel to the collector. It should thus be screwed onto the metal sheet or
next to the collector along an extension of the assembly rail. To this end, the sen-
sor case has a blind hole that can be opened at any time.
Line extension
All of the sensor cables with a cross-section of 0.75mm
2
can be extended up to 30m. Beyond
30m they can be extended by use of a suitably larger cross section. The sensor and the
probe can be connected by putting the heat-shrinkable sleeve truncated to 4 cm over a wire
and twisting the bare ends. Then the heat-shrinkable sleeve is put over the bare, twisted
ends and carefully heated (such as with a lighter) until it has wrapped the connection tightly.
Cable laying
In order to obtain interference-free signal transmission (to avoid measurement fluctuations)
the sensor lines must not be subject to interference factors. With the generally accepted use
of unshielded cables sensor lines are to be laid in their own cable channel at least 20 cm
away from mains cables.