ABB Millmate Rolling Force Measurement and Control System On site Troubleshooting and Maintenance Guide

For the PFVL series, the zero temperature drift index is ± 0.01%/℃. If the ambient temperature changes by more than 20 ℃, resulting in a zero point change of more than 0.2%, it is possible that the sensor temperature compensation component is damaged and needs to be replaced.

3.4 Overload or permanent damage

Phenomenon: The sensor output signal no longer changes linearly with the load, or there is a jamming phenomenon.

Reason: The actual rolling force exceeds 300% of the sensor's rated value (permanent data change) or 700% (mechanical damage). Commonly seen in severe steel jamming, overlapping rolling, or incorrect setting of rolling force.

Judgment: Use a known weight or hydraulic calibration device to calibrate the sensor. If the nonlinear error exceeds ± 1% (PFVL accuracy level is ± 0.5%) and the return difference is inconsistent after repeated loading/unloading, the sensor is damaged and must be replaced.

Chapter 4: Complete Process for Replacing Force Sensors

When it is confirmed that the sensor is damaged and the original model has been discontinued, please follow the steps below to replace it.

4.1 Record the key parameters of the original sensor

Search for existing equipment files or directly measure:

Rated load (MN)

Sensor type (circular/rectangular/circular)

Key dimensions:

Circle: outer diameter OD, inner diameter ID

Rectangle: Length L, Width W

Ring shape: inner diameter D2, outer diameter D3

Installation method: Does it come with a pre tensioning package

4.2 Select alternative models from the standard series

If the original load is 10MN, circular: PFVL 141C 10MN (OD=410mm, ID=360mm) can be directly selected. If the dimensions do not match, similar load specifications can be used, but it is necessary to ensure that the mechanical interface is compatible (transition flanges can be machined).

If the original load is 14MN, rectangle: Determine the size according to the formula L × W × 0.0001=14. If the original length is 420mm and the width is 330mm, then 420 × 330 × 0.0001=13.86, slightly less than 14. It is recommended to choose 440 × 330 or 420 × 340 (rounded).

For rings: it is necessary to ensure that D2 and D3 are completely consistent with the original mounting seat, otherwise the frame nuts or covers need to be reworked.

4.3 Matching Unit Replacement

Each PFVL 141 sensor requires a matching unit PFVO 142 (2 sensor scenarios) or PFVO 143 (4 sensor scenarios). The matching units are interchangeable, but it is recommended to use the same model when mixing old and new. The QGPR sensor requires the use of QIPZ 127 matching device.

Attention: The cable length of PFVO 142/143 is limited by the sensor load. For example, for a 20MN sensor, if 2 sensors are used, the maximum cable length is 22m; if 4 sensors are used, the maximum length is only 12m. When replacing, if the on-site cable length exceeds this value, the cable needs to be shortened or the number of matching units needs to be increased.

4.4 Cable Connection and Wiring

The cable between the sensor and the matching unit should be a specialized shielded cable provided by the manufacturer. It is recommended to use connector cables instead of fixed cables for easy replacement.

The shielding layer is grounded at one end on the matching unit side.

Avoid parallel wiring with power cables (>380V), with a minimum spacing of 300mm.

4.5 Controller Configuration

Enter the configuration menu of MC 400 through Operator Unit 410 or Ethernet VIP/TCP.

Select 'Measurement mode' as the standard mode (e.g. 'Roll force -2 load cells' or' 4 load cells').

Enter the rated load value (in MN) and type (PFVL 141C/V/R or QGPR) of each sensor.

Set filtering time. Recommend an initial value of 200ms and adjust according to actual stability.

Configure analog output: Select the signal type (0~± 10V or 4~20mA) and set the output range corresponding to the maximum force value (e.g. 0-10V corresponds to 0-20MN).

Perform zero calibration (press' Zero 'when unloaded).

Conduct simulation testing: Use Simulation mode to generate simulated force values within the controller and check if the display on the upper computer matches the simulated output. This helps verify whether the system integration is correct without the need for actual rolling.

4.6 Verification after replacement

Use a portable power source (such as a hydraulic jack+standard pressure sensor) to apply a known force to the rolling mill and compare it with the Millmate display value. The deviation should be within ± 0.5%.

Perform repetitive testing: Three loading unloading cycles, with a return error (lag) of less than 0.2%.

Record the new sensor serial number, replacement date, and configuration parameters, and store them in the equipment file.

Chapter 5 Maintenance and Self Diagnosis of Controller MC 400

The MC 400 controller is the brain of the system and supports multiple communication methods (analog, digital, Ethernet VIP, Profibus DP options). Common on-site malfunctions and their solutions:

5.1 Controller cannot start or restarts repeatedly

Check power supply: 85-264VAC, 100 (-15%)~240 (+10%). Low voltage can cause a restart.

Power consumption: 650VA in PFVL configuration, 140VA in QGPR configuration. Ensure sufficient capacity of UPS or power supply line.