User Manual

Siemens Building Technologies Application :37 RWD62/37 - 05.2001
HVAC Products RWD62 2
The temperature sensor senses the room conditions and on a fall in temperature
the RWD62 via Y1 analogue output modulates the hot water valve as determined
by the heating set point and proportional band (XP) setting.
On a rise in temperature the RWD62 via the Y2 analogue output modulates the
chilled water valve as determined by the cooling setpoint and the proportional
band (XP) setting
The auxiliary temperature sensor connected to (X2) senses the outside air
temperature, and when the temperature exceeds the O/A temperature set point,
the controller summer set point is selected, and Y1 output is changed from
heating to cooling. This results in extra cooling capacity during summer.
Heating and cooling sequences
Y1
Min V
Heating Setpoint
Ouptut
Voltagee
Cooling Setpoint
Max V
Cool ing
Y2
Max V
Min V
Heating
XP
XP
Cooling Setpoint
Y1
G
Y1
S1
D1
GO
Y..
BM
X1 X2MM
RWD62/3
0
X1
M
M
GO
G
24 V SN
24 V SP
N1
TOOL
PC
Y2
G
M
G
Y..
GO
Y2
X2
BM
G
RWD62
N1 RWD62 controller
X1 Main temperature sensor
X2 Outside air temperature sensor
S1 Time clock or switch
Y1 Heating / cooling control valve with 0..10Vdc input
Y2 Cooling control valve with 0..10Vdc input
PC Personal computer
Description of operation
Function diagram
Connection diagram