Eco Heating Systems CB 105 HW, Installation, Service And User Manual

Page: 67 / 147

E93.1803.901 HW 68
12.4 Explanation of the low voltage connections.
1-2 DO NOT USE
Do not connect wires to these terminals
3-4 SYSTEM SENSOR
Its mandatory (single and cascaded heaters) to use also a pipe strap-on sensor besides the tank sensor. This
system (Strap-on) sensor has to be connected to connections 3-
4 “System Sensor” (Cascaded heaters need
one system sensor connected to the managing boiler only.)
5-6 DHW SENSOR
The tank sensor can be mounted
in a bulb in the tank or glued to the tank dependent of the used type of
sensor
.
7-8-9 MODBUS
Connections for a MODBUS communication signal.
7 = ground, 8 = A, 9 = B (A detailed Modbus bulletin is available at your supplier on request)
10-11 AL-BUS DEPENDING
Cascade connections for the dependent water heaters, must be parallel linked together.
NOTICE: link all connections 10 to 10 and all connections 11 to 11, do not mix these.
Link connections 10 of the dependent water heaters to 20 of the managing water heater, and connections 11
of the dependent water heaters to 21 of the managing water heater.
12-13 DO NOT USE
Do not connect wires to these terminals
14-15 DO NOT USE
Do not connect wires to these terminals
16-17 DO NOT USE
Do not connect wires to these terminals
18-19 PWM
PWM pump signal, use this to control the pwm pump (Not used when an On/Off pump is used)
20-21 AL-BUS MANAGING
Cascade connection for the managing water heater.
Link connection 20 of the managing water heater to connections 10 of the depending water heaters, and con-
nection 21 of the managing water heater to connections 11 of the depending water heaters.
22-23 LWCO EXTERN
To be used for an extra external Low Water Cut Off. The water heater goes into a lockout when this contact
opens
24-25 GAS PRESSURE SWITCH
To be used for an extra external gas pressure switch. The water heater goes into a lockout when this contact
opens PARAMETER: water heater parameter 118, see: 11.9 "programmable in- and outputs"
26-27 SAFETY SWITCH 1
To be used for an extra external safety switch. The water heater goes into a lockout when this contact opens
28-29 SAFETY SWITCH 2
To be used for an extra external safety switch. The water heater goes into a lockout when this contact opens