Fisher 4194 differential pressure indicating controllers show process differential pressure and set point on an easy-to-read process scale.The controllers sense two different pressures and compare the difference between these pressures with an operator-adjusted set point. They are available for proportional only, proportional-plus-reset, and differential gap control. The controller is also available with anti-reset windup, internal auto/manual station, and remote set point adjustability. 4194 controllers are used in industries where process monitoring and accurate measurement of differential pressures are required.
FeaturesSimple design of the controller allows fast, easy maintenance and minimal spare parts inventory.Adjusting the set point and the zero and span of the process pointer and switching between direct and reverse action are accomplished quickly and without special tools.Simple design and low mass of internal parts allow the controller to withstand vibration encountered in most plant environments.Relay and nozzle design reduces steady-state air consumption to as low as 0.09 normal m3/hr (5 scfh).Tough plastic housing resists corrosive environments. Internal constructions are available to resist a corrosive supply pressure media.The controller can mount directly on the actuator or it can mount on a pipestand, on a wall, or in a panel.Two red pointers on a 114 mm (4 1/2 in) long white-on-black scale show differential pressure and deviation from set point at a glance. Two other gauges monitor supply and output pressures.
