SOMFY LT50 CMO Programming And Limit Setting Instructions page 3

Operator Wiring Considerations
Because of the type of motor (Asynchronous with built-in
capacitor) and the built-in limit switches, it is important to
follow two important recommendations to assure proper
operation of the motorized systems - SOMFY Operators
are not universal motors.
M1 Microswitch
M2 Microswitch
C Capacitor
W1 Motor Wiring
The operator is connected to a 120V-60HZ power source through a single
pole (or double pole), double throw, center off switch.
1. Do Not Wire SOMFY Operators in Parallel (Does not
apply to RTS or ILT motors). Parallel Wiring Means:
Several Operators are Wired to Only One Electrical
Contact Per Direction of Rotation.
There will be constant feedback from one motor to
another, so stopping points will not be stable and there is a
risk of motor burn out.
Correct:
Correct wiring solution is to use a double pole, double
throw, center off switch which would isolate both motors.
Incorrect:
Motor A stops at its limit in direction 2 before Motor B.
Current in Motor B feeds back to motor A through capacitor
C2 and microswitches M3 and M1. Both operators keep
rotating in opposite directions at reduced power.
2. Do Not Control One SOMFY Operator from Several
Locations Without Using Proper Controller.
Correct:
Possible problem: When switch (1) is turned on, the motor
will begin running in direction 1. As it reaches its limit, the
microswitch M1 will open. If, at the same moment in time
switch (2) is turned on, the motor will operate in the opposite
direction. This is why we recommend the use of momentary
switches with the Multi-Switch Command (MSC).
Incorrect:
The microswitch M1 closes, shortcircuiting the capacitor
which is loaded at its maximum voltage (180V). As a result
the microswitch M1 is damaged.
Solution: Use relays to build priorities between controls
sending opposite signals. Do not use a standard "light"
switch as a motor control.
NOTE: SOMFY Control Systems are designed to comply
with these two basic criteria and assure reliable operation
of motorized systems. Non-compliance to these two basic
principles voids the SOMFY warranty.
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SYMBOLS
W2 Motor Winding
TP Thermal Protector
GND Ground