DIFFERENTIAL PRESSURE
AND FLOW GAUGES

Switches and Relays:

Orange Research differential pressure and flow instruments are available with switches and relays to allow the user to be alerted of process conditions or control process equipment at pre-set values. We offer SPST, normally open or normally closed, and SPDT switches. 

Our switches are hermetically sealed reed switches and come with or without enclosures, depending on the model. The models with enclosures have all of the common safety ratings to satisfy a variety of environments and markets. Select from Nema-4X to Class 1, Division 1 or 2, or UL, CSA, CE, or ATEX ratings just to name a few. For complete safety ratings or certifications refer to our individual model Specifications Sheets.

Most of our reed switches are field adjustable within the upper 70 or 80% of the full-scale range of the instrument, depending on the model. Refer to our Specification Sheets for details on each model. All switches are preset to full-scale range unless another value is specified at the time of order placement. When two switches are used they can be set independent of each other.

Our relays are best for high inductive circuits such as those incorporating solenoids or motors. We use a reed switch to actuate the relay at a prescribed value. This isolates the reed switch, protecting if from high current or voltages. Some models allow for two relays on one instrument.

Relays Available for Explosion-Proof Switches

*Instruments that accept two reed switches can be supplied with one SPST and one SPDT switch if desired.

Refer to our individual model Specification Sheets for complete specifications listings.

Note:

Orange Research instruments use long life, hermetically sealed reed switches.  Depending on the load, reed switches can be expected to provide between 1-5 million operations at 240VAC/ 50W and 5-10 million operations at 110VAC/ 50W. 

To provide maximum life it is recommended that the proper contact protection be applied to reduce or eliminate arcing when switching inductive loads. For example, AC circuits could use a 100 ohm 1/4 W resistor and 0.1mfd, 600V capacitor in series across the contacts. For DC circuits use a 1N4004 diode (or equivalent) that is connected cathode-to-positive across the inductive load.

Ask about our High Voltage and High Temperature switches!

Refer to our Instruction Sheets for schematics on our switches and relays.

Transmitters:

Our instrument sensors include a magnet that moves with the sensor as the pressure or flow conditions change. Our transmitters incorporate a Hall effect sensor that transforms that movement into an electrical output. As the conditions change and the sensor moves into proximity to the Hall effect sensor there is a change in output from the Hall effect sensor that is proportionate to the DP reading or flow rate. 

Every transmitter is capable of providing a current and voltage output. The user simply selects the output they require. Temperature compensation ensures that the output of the transmitter does not drift.

Each transmitter can be installed as a two-wire (loop powered) or as a three- or four-wire voltage connection. The safety ratings of the switch enclosures also apply to the transmitters.

Download complete instruction sheet on our transmitters, including electrical connections (pdf).

Refer to our individual model Specification Sheets for complete specifications listings.