Belimo TRANE TAF Series, Technical Documentation Manual

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6
I20683 - Subject to change.
Control Signal Overview
Trane actuators are compatible with many control inputs. There
are many signals to select from with today’s controllers.
What does ‘on-off’, ‘open-close’, ‘3-point’, ‘tri state’, ‘floating point’,
‘proportional modulation’, mean?
Trane will help you understand more on this control signal
jungle with a quick overview:
On-Off or Open-Close: The actuator is able to drive either to
its full open position, or to its full closed position. The same
indication is used for Spring return type actuators. However the
actuator will drive to its full open position and spring return to its
zero position. This can also be reversed.
3-Point, Tri-state, Floating Point: The actuator has both clock-
wise (CW) and counter-clockwise (CCW) control inputs. One
drives the actuator to its open, the other to its close position. If
there is no signal (Null point) on either input the actuator simply
stays in its last position.
Proportional Control: The Actuator drives proportional to its
control input and modulates through-out its angle of rotation. This
control type is usually a variation of VDC. Common values are:
0-10 VDC 2-10 VDC
It is common to also have a 0-20 mA output from a controller.
This can be very easily converted to 0-10VDC or 2-10 VDC
with a 500
Ω
resistor.