1. Stroke of electric actuator.
This parameter is also an important parameter. For the angle stroke electric actuator, the stroke is fix at 0-90 degrees. For the straight stroke, the stroke unit is mm. It needs to determine according to the stroke of the regulating valve core. The normal stroke of the straight stroke electric actuator (electric actuator) has the following gears: 10 mm, 16 mm, 25 mm, 40 mm, 60 mm, 100 mm. For multi turn electric actuator (electric actuator), generally, the number of turns of this actuator can meet the requirements.
2. Electrical interface.
To determine the control mode of electric actuator (electric actuator), what kind of signals need to be fed back by the electric actuator (electric actuator).
3. Control mode.
(1) Analog quantity control.
Generally, the analog quantity control is 4 ~ 20mA, and 0 ~ 10mA, 1 ~ 5V, etc. the latter two are not used much now. Generally, the adjustable electric actuator can be controlled by analog quantity.
(2) Switching value control.
Generally, the switch control signal is “on” and “off” command signal, and there may also be “stop” command signal. The switching value mainly includes the following: passive, 24V DC, 220V AC. generally, if equipped with servo amplifier, the switching value is required to be 220V AC.
4. Feedback signal.
(1) Analog feedback.
Analog valve position feedback signals are the valve position feedback signals corresponding to the current valve position output by the electric actuator (electric actuator). There are also 4 ~ 20mA, 0 ~ 10mA, 1 ~ 5V. The latter two kinds are rarely use now. Generally, analog valve position feedback signals are require for servo amplifiers.
(2) Switch value feedback signal.
According to the process requirements, it may be necessary for the electric actuator to output a fully closed and fully open switch signal, and even other meaningful signals, such as actuator fault alarm signal. In general, the switching value is passive, but there are also active.
In addition to several important parameters mentioned above, some parameters are not so important, but may be very important according to the process requirements, such as installation size, weight, control accuracy, full stroke time, protection level, etc.