Baker Hughes DNGP Series 3-5 - Digital Natural Gas Positioner DNGP Series 3.5

All solenoid operators and valves should be cleaned periodically. The time between cleaning varies depending on medium and service conditions. In general, if the voltage to the solenoid is correct, sluggish valve operation, excessive noise or leakage indicates that cleaning is required. Clean strainer or filter when cleaning the valve.;

- Faulty Control Circuit: Check the electrical system by energizing the solenoid. A metallic click signifies that the solenoid is operating. Absence of the click indicates loss of power supply. Check for loose or blown fuses, open circuited or grounded solenoid, broken lead wires or splice connections.

- Burned Out Solenoid: Check for open circuited solenoid. Replace if necessary. Check supply voltage: it must be the same as specified on nameplate/retainer and marked on the solenoid. Check ambient temperature and check that the core is not jammed.

- Low Voltage: Check voltage across the solenoid leads. Voltage must be at least 85% or rated voltage.;

1. Switch DNGP to Standby from Auto. Observe feedback mA indicator. If position of the valve changes, continue to step 2.

2. Move MCV to Manual to close the block valve or close the cylinder block valves.

3. Check the cylinder for decaying or equalizing pressure. If cylinder pressure is: • Decaying - check and repair leaks at fittings. • Equalizing - rebuild the cylinder.

4. Check for external leak at gasket and NPT instrumentation ports: • If a leak is found - tighten bolts or fittings. • If no leak is found - check the solenoid valves.;

- Keep the medium flowing through the solenoid operator or valve as free from dirt and foreign material as possible.

- While in service, the solenoid operator or valve should be operated at least once a month to ensure proper opening and closing.

- Depending on the medium and service conditions, periodic inspection of internal valve parts for damage or excessive wear is recommended. Thoroughly clean all parts. Replace any worn or damaged parts.;

Replacing the Electronic Module of the Programmable

1. Turn off the power and remove the four connecting wires.

2. Remove the two retaining screws with a 3 mm hex wrench.

3. Remove the Electronic Module from the housing and shaft.

4. The new transmitter module can be either 20 mA Down or 20 mA Up depending on the position of Dip Switch #2 (See Figure 34).

To program the transmitter to the: • 20 mA Down mode (the 20 mA signal is generated at the end of the shaft): Dip Switch #2 is down or off. • 20 mA Up mode (the 20 mA signal is generated close to the body): Dip Switch #2 is up or on.

5. Insert the new electronic module back on the transmitter housing, connect the four wires and turn the power to On.

6. Insert the two screws with hex wrench, connect the wires and power the unit.;