United Electric Controls Differential Pressure Switch J120-270-274

⚠ Important Safety Instructions

Ensure the following safety precautions are met before wiring

Verify the internal grounding terminal is used as the primary equipment grounding means

Ensure the external grounding terminal is only used for supplemental grounding connection if permitted or required by local authorities

Remove cover and wire device as per Figure 3

Wire directly to the terminal block

Locate internal grounding terminal near the right-hand conduit opening

Replace cover and hand tighten to fully engage cover O-ring

Ensure you have the following tools

Connect device to a calibrated pressure source

Loosen Phillips screw adjustment lock

Secure adjustment screw by tightening adjustment lock

Tools Needed: Screwdriver/Adjustable Wrench to 1-1/2"

Read and understand all instructions before device installation.

Check sensor model for compatibility with process media and wetted parts.

Disconnect supply circuits before opening to prevent ignition of hazardous atmospheres.

Ensure proof pressure limits are not exceeded, even by surges.

Wipe down cover and enclosure to prevent electrostatic discharge.

Install device where shock, vibration, and temperature fluctuations are minimal.

Mount device to prevent moisture entry and use explosion-proof sealing fittings.

Remove front window and gasket (four screws) to gain access to span adjustment

Connect device to calibrated gauge and set required differential pressure

Using a screwdriver, slowly turn the span adjustment to obtain required indication

Remount the front gasket and window

Spanning adjustment will not affect the mid-range indication. The adjustment is factory calibrated and sealed to indicate tampering.

DO NOT FORCE SPAN ADJUSTMENT, SINCE PERMANENT DEFORMATION OF THE LINKAGE MECHANISM MAY RESULT.

Determine Set Point and Deadband Values

Enter the desired rising set point (psi)

Calculate the falling set point by subtracting the deadband value from the desired set point

Set the falling set point using the standard adjustment screw

Turn the adjustment wheel clockwise to increase or counter clockwise to decrease the setting