FISHER 4200系列位移变送器

一.简介

the 4200 series electronic position transmitters combinefisher’s field-proven electronic and mechanicalexpertise in a versatile, accurate instrument thatsenses the position of a device, and sends a standard(4 to 20 milliampere)output signal to an indicating device.the instrument is available as a transmitter withintegral high and low electronic travel limit alarms, as atransmitter only, or with electronic travel limit alarmsonly.

the instrument can sense the position of rotary or slidingstem valves, vents, dampers or other devices.when the instrument is mounted, a potentiometershaft is mechanically connected to the device to sensemechanical motion. for a standard instrument, asingle potentiometer is provided for position input, or an optional dual element potentiometer is available to allow independent electrical operation of the transmitter and alarm circuits.

the instrument has standard, or long stroke (see figure 5), capabilities for sliding stem actuator applications.
for long stroke applications, a multiturn potentiometer attached to a cable/pulley assembly is used to sense linear motion of the actuator stem or other devices. the instrument with standard capabilities can also be used on actuators.

for instruments e with electronic travel limit alarms, individual electronic high and low alarm circuits
drive separate high and low alarm spdt relays. the user adjusts the trip point and deadband of the high and low alarms to the desired travel limits. when the sense potentiometer voltage is higher than the high trip point, the electronic high alarm circuit de-energizes the high alarm relay. when the sense potentiometer voltage is lower than the low trip point, the low alarm circuit de-energizes the low alarm relay. the low trip point may be offset from the high trip point by as little as 5% of the remaining span. in the event of a power loss to the alarm circuits, both alarms are tripped (both relays are de-energized). this indicates a available configurations.

二.具体型号及分类

应用于角行程的有：4210，4211，4212，4215
应用于直行程的：4220，4221，4222