
Siemens
Product Guard
Warranty
SQS Electronic Valve Actuator
24 Vac, Floating Control
Spring Return
Powermite
MT Series Globe
Powermite MT Series SQS85.53U
Electronic Valve Actuator
Description
The Powermite SQS85.53U electronic valve actuator
requires a 24 Vac supply and receives a oating control
signal to provide oating control. This actuator works with
Powermite MT Series terminal unit valves with a 7/32-inch
(5.5 mm) stroke.
Features
• Maintenance-free with reversible motor
• UL listed for plenum installations
• Close off up to 160 psi
• Floating control signal input
• Mechanical spring returns the valve to its normal
(spring return) position in power off condition.
• Suitable for liquid and low pressure (15 psi)
steam applications
• Orderable as an actuator only or as a complete
valve/actuator assembly
Applications
For use in small to medium HVAC installations with
Powermite valves with a 7/32-inch (5.5 mm) stroke
requiring a minimum of 90 pounds force (400 N). These
valves can be used in liquid and low pressure steam
service applications.
Recommendation:
Use only with the MT Series valve bodies. This actuator is
not recommended for 2-position or pulse applications.
A-153
Valves
Siemens
Product Guard
PLUS 3 Warranty
www.usa.siemens.com/hvac

SQS85.53U Actuator Specifications
A-154
Operating Voltage
60 Hz .....................................................................24 Vac, + 20%, -15%
Frequency ....................................................................................... 60 Hz
Power Supply ......... Earth Ground Isolating, Class 2, 24 Vac Transformer
Power Consumption ......................................................................... 5 VA
Control Signal ...............................................................................Floating
Y1 ................................... 24 Vac, Power Extends Actuator Shaft (0 to 1)
Y2 ...................................24 Vac, Power Retracts Actuator Shaft (1 to 0)
Running Time at 60 Hz ..................................................................30 sec.
SQS85.53U Actuator Product Ordering
Description Part No.
Floating 3P Spring Return SQS85.53U 266
There are no repair parts for this product.
Replace the entire actuator if inoperative.
Actuator
Prex Code
Dimensions
Nominal Stroke .................................................................7/32" (5.5 mm)
Nominal Force ...................................................................90 lbf. (400 N)
Spring Return Time ....................................................................... 8 sec.
Agency Approvals ........................................................... UL/cUL, UL873
CSA C22.2 No. 2A-93
Ambient Temperature
Operation.......................................................... 23 to 122°F (-5 to 50°C)
Transport and Storage ..................................-13 to 149°F (-25 to 65°C)
Ambient Humidity .................................... 0 to 90% RH, Non-condensing
Wiring Connection .............Plenum Cable or Conduit via a 1/2" Knockout
Mounting Location .............................................. NEMA 1 (Interior Only)
Center Line to
Valves
Valve Size
in.
1/2" (15 mm) 6-1/16" (153 mm) 14" (355 mm) 5-1/16" (128 mm) 9" (225 mm)
3/4" (20 mm) 6-1/16" (153 mm) 14" (355 mm) 5-1/16" (128 mm) 9" (225 mm)
1" (25 mm) 6-5/16" (159 mm) 14-1/2" (370 mm) 5-1/16" (128 mm) 9" (225 mm)
Service height and width are the recommended dimensions to allow access to the product.
Top of Actuator
1
H
NO NC
NO NC
Service
Height
H W
Dimensions shown in inches (mm).
Actual Width
of Actuator
Service
Width
1
W
Accessories & Service Kits
www.usa.siemens.com/hvac
A-257