User Manual

2
Siemens
A6V11858863en
Smart Infrastructure
2019-11-21
Use
The PTC conductive heating element ASR70 is used as an accessory on modulating
refrigerant valves:
● MVS661…
● MVL661…
ASR70 extends the application range of valves for refrigerant temperatures at the valve inlet
below 0° C. Typical applications include pump systems with ammonia or CO
2
refrigerant
machines.
The heating element must be under power as long as the refrigerant temperature at the
valve inlet is below 0° C and is below the valve’s ambient temperature.
The heating element can be switched off when a plant is switched off and the ambient
temperatures are below 0° C or when operating refrigerant temperatures above 0° C at the
valve inlet.
PTC conductive heating elements are not intended for use in potentially explosive atmos-
pheres.
PTC conductive heating elements in potentially explosive atmospheres are not certified nor
approved for use as per ATEX regulations.
Functions
Dynamic heating element to heat solids in very small areas.
Type summary
Type
Stock number
Operating
voltage
Power
consumption
1)
Switch-on
current max.
IP
Cable
ASR70
S55845-Z241
AC / DC 24 V
30...45 W
5 A
54
Fixed connecting cable 1.4 m
(2 x 0.75 mm
2
)
1)
Actual power consumption is based on the temperature of the U-bracket, see Technical data, page 4
Delivery
S55845-Z241: PTC conductive heating element ASR70 with two-sided conductive tape and
clip are included in the package.
Order example
Type
Stock number
Designation
Number
ASR70
S55845-Z241
PTC conductive heating
element
1
Equipment combinations
Ventiltyp
MVS661.25-016N
Modulating refrigerant valve with magnetic actuator, PN 63
MVS661.25-0.4N
MVS661.25-1.0N
MVS661.25-2.5N
MVS661.25-6.3N
MVL661.15-0.4
Modulating refrigerant valve with magnetic actuator, PS45
MVL661.15-1.0
MVL661.20-2.5
MVL661.25-6.3
MVL661.32-10
MVL661.32-12