How to Test Pressure Transmitters and Switches.

Using a Crystal meter with a hydraulic hand pump.

Rosemount 3051 Pressure Transmitter Test

• Notify Control Center of Test and Lock Out Tag Out.

• Sample Air with Gas Monitor• Make sure Crystal Calibration is up to date• Set up Crystal meter Scale to show milliamps

and pressure. • Use Setup button on meter to change upper

and lower units to find proper test screen.

Crystal meter setup for pressure transmitter test.

Crystal Screen for Transmitter test showing milliamps and pressure.

Positive lead connects to test point on Transmitter and negative lead to negative on transmitter.

How to connect hand pump and set up manifold valves to test Transmitter.

Connect Hand Pump to Vent Test Point on Transmitter Manifold.

Close (blue) Isolate valve on manifold and open (red) vent valve to test.

AMETEK hand pump made for Crystal MeterThe hand pump has two valves on the side and one controls the release of pressure and the other is a fine adjustment to build pressure or release pressure. It will take several pumps on handle to build max pressure to test a pressure transmitter. To get a good zero at beginning you will have to remove the fill cap on top of fluid reservoir. The fluid in reservoir is like – kind which means its filled with local crude oil. It will take a little practice with pump to get efficient at testing.

Check Transmitter Pressure at 4ma, 12ma, and 20 ma with hand pump.

4ma crystal reading at zero pressure. Half Scale Reading (12 ma)

Pressure Transmitter Manufacture Tag With Calibration Information

Record Transmitter Calibration Data for DOT Station Check

• The Pressure Transmitter Calibration plate and Station PLC Settings should match the 4ma and 20 ma calibration points just found with the crystal meter.

• Set up Crystal meter to record by touching record button and typing name of transmitter testing. Once the check is selected on key board screen the meter will record.

• Record from (4ma) zero pressure to half scale (12 ma) and then to full scale at (20 ma) using hand pump. At half Scale verify with control center that the meter value matches what is seen on their screen for that transmitter. Release pressure on Transmitter to zero and hold record button until meter stops recording. Close vent valve on manifold and disconnect pump. Open Isolation valve on manifold and test is done.

Pressure Transmitter Graph Recorded by Crystal Meter.

How to Set Up Differential Pressure Manifold to Test Transmitter.

Steps to Set Up Differential Pressure Manifold.

• Close Inlet and Outlet Valves to Manifold. Not in previous picture. Leave Isolation Valves open (blue)

• Open Equalize Valve (Green) on manifold.• Open Down Stream Vent. A little fluid will be released.• Remove up stream vent and connect hand pump here.• Close Equalization Valve (green) on Manifold.• Test Transmitter.• Open Equalize Valve (green) on Manifold.• Remove hand pump and reconnect up stream vent.• Close all vents.• Open Inlet and outlet valves.• Close Equalizer valve( green) on Manifold.

Pressure Switch Schematic For Testing

Crystal Meter Pressure Switch Set Up Positive lead is in voltage connection for continuity test through pressure switch.

Meter is set up for pressure and switch position.(Set up- choose units- choose upper units, use arrow to get switch)

Steps on Testing Pressure Switch at Pump.

• Remove the two wires connected to pressure switch.• Connect meter leads at these locations. The switch on meter screen should be

closed with zero pressure.( Normally closed contact )• Connect hand pump to pressure switch manifold. • Use hand pump to add pressure to switch.• The pressure switch should open when pressure reaches set point. At this point

the crystal meter switch will show to be open.• Adjust pressure switch if not within set point established by Operations and

retest. • Set up Crystal to record and conduct three tests of switch opening at set point

pressure.• Remove hand pump from pressure switch manifold and disconnect meter from

switch.• Reconnect wires to pressure switch.

Crystal Meter Pressure Switch Test Graph

UE One Series Pressure Switch

UE One Series Set Up Instructions

Set upper limits on Crystal to measure voltage and lower units pressure.

5 volts when switch is closed 24 volts when switch opens

UE One Series Pressure Test

Connect Crystal Meter leads to positive and negative posts on UE One series meter.The meter should read 5 volts at this time.Connect hand pump to test port and add pressure until switch opens at set point pressure. The meter should read 24 volts with a open switch. Record test three times.

UE One Series Test Results Recorded

DAVID AAKRETECHNOLOGIST

Don’t forget to keep a record of your testing. Be safe and sample air before opening any intrinsically safe instrument.