General - Siemens RVW26.000B27 Basic Documentation

Short description
Siemens Building Technologies
HVAC Products
3

General

The electronic control units RVW25... and RVW26... are designed for air / fuel ratio
control in connection with modulating burners.
They use a variable speed drive for controlling the fan motor, actuators for driving the
fuel control valve and – optionally – an additional actuating device, depending on the
required burner output.
The RVW25... and RVW26... ensure that the air / fuel ratio and the position of the aux-
iliary actuator (AUX) correspond to the programmed curves across the burner's entire
working range.
LR
DC 0...10 V
78731m01/0601
Fig. 2 Basic diagram of burner control, load controller, RVW25... and RVW26...
The RVW26... must always be used in connection with a burner control, an RVW25...
and a load controller that delivers either a 3-position or DC 0...10 V control signal.
Both burner startup and burner shutdown are controlled by the burner control.
The RVW26... is designed specifically for use with our burner controls, for safety rea-
sons, the control sequence of the signals must be fully adhered to.
When commissioning the burner, the RVW26... can be matched to the burner plant by
making the relevant parameter settings.
The parameters are set with the help of the handheld terminal AZW20.20.
Outputs «AUX1» and «AUX2» can be used to control an additional actuating device,
such as a primary air damper, an adjustable head, or a flue gas damper.
Electronic Air / Fuel Ratio Control System
3 General
FA
RVW25
M M
AUX FUEL
RVW26
FU M
G
TG
AUX1
CC1P7873.1en
M
AUX2
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15.10.2002