Kessel Comfort PLUS Original Operation Manual page 50

Connecting the level sensors
Mono/Duo level sensor (non-ATEX)
Connect the ends of the level sensor cables "Fig. [21]".
The connection of level sensors is identical for both Mono and Duo systems.
50
Overview of connections for the level sensor
Wire colour
(-)Black
(+)Red
Note: When extending the level probe connection cable, use the
KESSEL terminal box (art. no. 28799).
Fig. [21]
Installation and operating manual
Name on PCB Terminal colour
Probe2
black
Mono/Duo
blue
(-)
sw/BK
(+)
rt/RD
010-700_01