Data Sheet for Product

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Siemens Frost detector‘ A6V10432022_en--_e
Smart Infrastructure 2021-04-20
Three operating modes can be selected:
If, after shutdown due to frost, the capillary tube temperature rises (>2 K), the out-
put relay will automatically return to its normal position.
If, after shutdown due to frost, the capillary tube temperature rises (>2 K), the out-
put relay will return to its normal position only if either the inbuilt reset button is
pressed or the power supply is cut off (e.g. via an external reset button).
In test mode, the output relay is forced to the "Frost" position. The valve control sig-
nal Y10 will not be affected.
When returning to the switch position "Manu", the frost position is maintained. It
must be cancelled by pressing the reset button.
The frost detector offers different operating modes, allowing different setpoint ad-
justments:
 "Auto" = automatic operation (normal position)
 "Test" = frost simulation via button
 "Manu" = manual function
In manual mode, only trained personnel are allowed to change the setpoint.
(1 ) Display 7-segment display, 2 digits, red
( 2 ) Indication of switch position 1 LED for relay output
( 3 ) Buttons To operate and set the frost detector
and to make the reset in manual mode
Designation Display Factory setting Value range
Switching point Sp 5 °C 1…10 °C
Operating mode St Automatic Automatic (at)
Manual (hd)
Mechanical design
The frost detector consists of a two-sectional housing (base and cover) and a capil-
lary tube which is active over its full length.
The cover is secured to the base with a fixing screw and can be removed.
The housing accommodates the electronics, the diaphragm with the heating ele-
ment, the setting elements, the connection terminals and the type field.
Connection terminals, setting elements and type field can be accessed after re-
moving the cover.
The cables are introduced to the housing from below. There is one hole for the en-
closed cable gland M16, and 2 knockout holes for additional cable glands M16.
The QFA64.. can be fitted directly to the wall – with or without a test loop – or with
the help of a mounting flange (if the air duct is insulated).
Operating modes
Automatic operation
"Auto"
Manual operation "Manu"
"Test" mode
Display and setting ele-
ments
Operating modes
CAUTION
Parameters and
configuration