GE DC Drives (BCH series) upgrade and replacement of old DC drives

Check if the wiring is twisted pair shielded and if the shielding layer is grounded at one end.

Viewing the original AD value in P80i software, if there is significant noise displayed, it may be due to interference from the frequency converter.

6.4 Periodic speed oscillation of motor

Possible reasons:

The PI parameter ratio of the speed loop is too large or the integral is too small

Loose coupling of speed encoder or signal interference

exclude:

Temporarily halve the proportional gain of the speed loop and observe whether the oscillation weakens.

Check the installation of the encoder and the grounding of the shielding layer.

Plot the given speed, actual speed, and current simultaneously in the P80i trend window, and analyze whether the oscillation frequency is consistent with the mechanical resonance point.

6.5 Intermittent communication with upper PLC

Possible reasons:

Network cables are too long or of poor quality

IP address conflict

High network load leads to packet loss

exclude:

Check the length of the network cable (<100m) and use a professional tester to measure signal attenuation.

Put the driver and PLC into the same VLAN and broadcast them separately.

Check the packet loss rate on the Ethernet diagnostic page of PECe (should be<0.01%).

Service and Support: Ensuring Long Term Availability

Upgrading cannot be just a one-time project, long-term maintenance capability is equally important. GE provides the following services:

24/7 Global Support Center: Telephone or online remote diagnosis.

Visor Connect remote support system: Through the secure satellite/Internet link, experts can remotely view the screen of field engineers to guide troubleshooting.

Spare parts strategy: Key components such as PECe, PIBe, and power modules are stocked in regional warehouses and promised to be shipped within 48 hours.

Regular health check: Conduct on-site or remote check ups once a year, including parameter backup, waveform recording, and thermal imaging inspection of power devices.

Training: Provide beginner and advanced courses (including practical exercises) for maintenance engineers.

For extremely old systems that are completely irreparable (such as early analog SCR control), GE also provides turnkey replacement services, including on-site surveying, new cabinet design, installation and commissioning.

Rated value and selection reference

When upgrading, it is necessary to ensure that the new controller is compatible with the voltage and current levels of the existing power section. The following are some specifications of GE BDM series air-cooled DC drives (as a reference for replacing power stacks):

Model Input Voltage Vac Rated Current A 150% Overload (60s) A 200% Overload (60s) A Power kW Weight kg

BDM4-250 183Vac / 229Vdc 322 483 532 137 46.7

BDM4-525 575Vac / 700Vdc 357 480 - 288 104.8

BDM4-1200 846Vac / 1097Vdc 610 976 - 581 112.9

For higher voltages (6000V) or greater power (2500kW), a cabinet style integrated system with UL/CE certification can be provided.

Selection suggestion:

If you want to keep the existing motor and transformer, when upgrading the control part, you can choose PECe+PIBe without replacing the power stack.

If the original power stack has aged or has insufficient capacity, a new BDM series can be chosen to replace it, and its mechanical dimensions are compatible with common old-fashioned DC cabinets.