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Siemens Building Technologies
Electronic Air / Fuel Ratio Control System
CC1P7873.1en
HVAC Products
17 Engineering notes
15.10.2002
17.2 Engineering
Separate
cables must be used for low voltage lines on the one hand and mains voltage
lines on the other.
Low voltage lines should not be run parallel to mains voltage lines when long distances
are involved (disturbances).
The lines to the feedback potentiometers in the actuators must be shielded (including
those in the control panel).
The shielding must be connected on only one side, namely to terminal «M» of the
RVW26...
It must
never be connected
on the actuator side.
There must be
no electrical
connection between terminals «N» and «M» and between
«M» and «PE».
The maximum permissible line length is 100 m.
The lines to terminal «X2» (application of correcting variable) and to terminal «U1»
(analog input for burner output) should also be shielded, with the shielding connected to
terminal «M» of the RVW26...
The RVW26... should be mounted such that its display is visible (error code, etc.).
The actuator running times must lie between 30 and 60 seconds..