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Above values are indications and depend on the insulation thickness.
Complete the heating cable tests (including the insulation resistance
test) in accordance with 5.4 (Checklist
for problem-free installation and safe
operation).
2.3.4 Boiler- Temperature Sensor
(KTY or PT100)
The temperature sensor must be
connected to a single or master unit
only. Connect both wires of the sensor
to the TEMP terminal in the unit, see
Fig. 4. The sensor wires do not have
a special polarity. To connect a wire
use a screwdriver to push down the
orange tab on the side of the terminal.
Put the wire into the hole and release
the orange tab. The sensor should be
connected as near as possible to the
boiler (5.5 Diagrams).
The metal tabs can be folded around
the hot water output pipe. Use the
aluminium tape (included) to attach the
sensor to the pipe. The sensor andat
least 200 mm of the sensor cable
should be covered by insulation.
See diagramm A. Be careful not to install the heating cable too close
to the sensor, keep a clearance of at least 200 mm. The standard
temperature sensor cable can be extended up to 100 meter. The
extension cable should have a basic insulation of 500 V and a solid core
of at least 0,75 mm² (@ 100m). The optional PT100 sensor cable must
not exceed 20 meters (Fig. 4).
2.3.5 Alarm wiring
The alarm contact (24 VAC, 24 VDC, 1A) inside the unit can be used to
switch an external device. The contact can be selected for NO or NC
operation. In a network all alarm contacts should be connected in series.
The alarm terminal is located in the upper right corner of the unit and has
the text “alarm contact” next to it. To connect a wire use a screwdriver
to push down the orange tab on the side of the terminal. Put the wire
into the hole and release the orange tab. The wires used for the alarm
contact should have a dielectric strength of 500 V.
See Chapter 4 for alarm relay conditions.
Note: For master/slave combination with alarm function, the alarms
need to be connected in series by a RS485 shielded wire. Due to the
limited amount of holes in the sealing ring of the cable gland, the alarm
wire and BMS wire can be combined in a 4 wire cable.
NC NO
Alarm contact
C
Standard temperature sensor
short
for
PT100
PT100 sensor (2 wire)
BA
BMS
TEMP
BA
BMS
TEMP
Terminals
inside the
HWAT-ECO.
Fig. 4