RMC150E Troubleshooting an Open Gear Absolute Loop

Tom Garrett2 min read
Delta ElectronicsMotion ControlTroubleshooting
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Reported RMC150E Configuration

The application uses one servo valve to port fluid to two cylinders. A string transducer measures the front cylinder, and a second transducer measures the rear cylinder. The reported setup uses the Proportional value as the CV and configures Gear Absolute (25) with a 1:1 ratio. The axis and controller are enabled, but the loop continues to indicate “Open.”

Item Evidence Engineering status
Hydraulic output One servo valve serving two cylinders Confirmed
Feedback One string transducer per cylinder Confirmed
Command Gear Absolute (25), 1:1 ratio Confirmed
Enable state Axis and controller enabled Confirmed by report
Control objective Individual, average, or another position relationship Not specified
Axis definitions and tuning No configuration details supplied Must be verified

Resolve the Control Objective First

The available evidence does not identify one omitted setting. Before changing the command, define whether the valve must control one cylinder’s position, the average of both positions, or another relationship between the two transducers. With one control output and two feedback measurements, that decision determines how the axes and controlled variable must be defined.

Do not assume that enabling the axis and controller alone establishes closed-loop operation. The evidence confirms only the reported enable state; it does not establish that the selected axis definition, feedback relationship, or Gear Absolute command is sufficient to close the loop.

Check Axis Definition and Tuning

  1. Document the intended controlled quantity: individual cylinder position, average position, or another defined relationship.
  2. Review how both axes are defined and identify which feedback value participates in the control loop.
  3. Verify whether the controlled axis has been tuned. The supplied evidence does not confirm that tuning was completed.
  4. Run the application again and verify whether the loop changes from “Open.” Record the axis definitions, command state, feedback values, CV, and resulting loop indication.

Escalate with the Complete Project

If the loop remains open after the control objective, axis definitions, and tuning state are verified, send the project files to Delta Motion technical support at [email protected]. Include a concise description of the desired cylinder relationship and identify how each axis, transducer, and the single servo-valve output is configured. This gives support the information needed to find an omitted or inconsistent project setting.

FAQ

Why does my RMC150E loop remain Open after enabling it?

The evidence does not identify a single missing setting. Verify the control objective, axis definitions, feedback participation, and tuning state before concluding that Gear Absolute (25) is misconfigured.

Can Gear Absolute (25) use a 1:1 ratio for two cylinders?

A 1:1 ratio is the reported configuration, but the evidence does not confirm that it implements the required relationship for one valve and two position transducers. First define whether the system controls an individual position, an average position, or another relationship.

What should I send Delta Motion support for an RMC150E open-loop problem?

Send the project files to [email protected] and describe the intended control relationship, axis definitions, transducer assignments, tuning state, Gear Absolute (25) configuration, CV, and observed “Open” indication.

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