Viessmann VITOCAL 300 Installation And Service Instructions Manual page 136

Connection and wiring diagrams
Safety chain
(cont.)
E Implemented as individual free
core outside the PCB
F On relay contact K1 on the control
PCB (see page 137)
G Jumper (or optionally for DHW
version: Frost stat and flow
switch)
eP Brine pressure switch
eQ Power-OFF (accessory)
eW Thermal overload relay, primary
pump
*1
If not connected, insert the jumper supplied between terminal 5 and 6.
*2
If not connected, insert the jumper between terminal 7 and 8.
*3
If not connected, insert the jumper between terminal 1 and 2.
136
eE Safety high pressure limiter, com-
pressor
eR Low pressure, compressor
eT Control high pressure, compres-
sor
eZ Thermal overload relay, compres-
sor
tO Frost stat/flow switch in series (for
* 1
* 2 type WWC) * 3