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Siemens Building Technologies
Electrical Actuators
CA1N4895en
HVAC Products
08.03.2004
When first connected to power, or
after a power failure, the capacitor
which stores energy for the fail-safe
function will be charged. This process
takes up to 180 seconds. While the
capacitor is being charged, the
actuator cannot respond to any Y
control signals.
max 180 s
max
30 s
Charging
Calibration
Discharge
48
95Z01
en
Stroke
[
%
]
100
0
t
60 s
Normal
actuator
operation
On completion of the charging process and auto calibration (see below), the "Open"
and "Close" travel are proportional to the DC 0…10 V control signal.
In the event of a power failure of more than 5 seconds, the actuator will return
mechanically to its 0 % stroke position within 30 seconds, closing the valve
(A
→
AB).
When the AC / DC 24 V supply is applied for the first time, the actuators calibrate
themselves independent of the control signal. In this process, the actuator drives the
valve to the mechanical end stops and stores the associated positions permanently in the
form of electronic values. The positioning signal is only active on completion of this
calibration process. Calibration takes about 60 seconds.
The SSC61.5 only performs auto calibration when the charging process of 180 seconds
is completed.
If the calibrated actuator is used with
some other valve (e.g. a replacement
valve), it must be recalibrated. For that
purpose, the PCB beneath the terminal
cover has a slot (see illustration). To
make the recalibration, use a
screwdriver and connect the 2 contacts
behind the slot for about 1 second.
3
2
1
48
95
Z
02
The calibration can only be made correctly if the actuator is fitted to a valve (refer to
«Equipment combinations»).
•
Plastic cover
•
Locking-proof, maintenance-free gear train
•
Manual adjustment with rotary knob
•
Reduced power consumption in the holding positions
•
Load-dependent switch-off in the event of overload and in stroke limit positions
Accessories
Type ASK30
Electrical fail-safe
function
SSC61.5
Auto calibration
SSC61 and SSC61.5
Recalibration
Features and benefits
Mounting kit