Board 6RY1703-0CA01 C98043-A7014-L2 6RY17030CA01 C98043A7014L2 6RY17O3-OCAO1 C98O43-A7O14-L2 6RY1 703-0CA01

Siemens 6RY1703-0CA01 | SIMOREG DC-MASTER 6RA70 Field Supply Board — C98043-A7014-L2 Excitation Control Card

Market Order Number: 6RY1703-0CA01

Internal Component: C98043-A7014-L2 (variant -4)

Manufacturer: Siemens AG (Germany)

Product Type: Field Supply Board — Excitation Control Card

Controlling the Motor Field

The 6RY1703-0CA01 is the field supply board for the SIMOREG DC-MASTER 6RA70 DC drive. Its function is to generate and regulate the DC current through the DC motor's field winding. The field current — also called excitation current — establishes the magnetic flux in the motor. Without correct field excitation, the armature current cannot produce torque efficiently, and field weakening above base speed is not possible.

The board uses a single-phase half-controlled thyristor bridge to convert the incoming AC supply into a regulated DC field output. The CUD1 control board sends firing commands to the field supply board, adjusting the phase angle of the thyristor firing to control field current magnitude. In field-weakening operation, the field current is progressively reduced as speed rises above base speed.

Drive Range and Application

The 6RY1703-0CA01 (C98043-A7014-L2) serves 6RA70 drives in the 140A to 510A current range at standard 460V. Smaller drives (15A–100A) use a different field supply board variant. Very large drives (850A and above) use a separate high-current field supply board with a different C98043-A7004 component designation.

Always confirm the drive's armature current rating from its rating plate before ordering a field supply board replacement.

Key Specifications

FAQ

Q1: The SIMOREG shows F038 (field current too low) or motor runs at high speed with no speed command. Is the field supply board likely at fault?

F038 and uncontrolled overspeed are both classic symptoms of lost or reduced field excitation. A failed field supply board results in low or absent field current. Confirm by measuring the actual field current at the motor terminals with a clamp meter. Absent or significantly low field current with normal field supply voltage points to the C98043-A7014-L2.

Q2: Is the 6RY1703-0CA01 interchangeable with the field supply board for 850A–1660A drives?

No. The 850A–1660A drive uses C98043-A7004-L1 (order number 6RY1703-0EA01), a separate high-current variant. The C98043-A7014-L2 is specified for the 140A–510A range only. Fitting the wrong variant causes incorrect field current regulation.

Q3: Can the field supply board be replaced without affecting CUD1 parameters?

Yes. The field supply board does not store drive parameters — all settings reside on the CUD1. After fitting the replacement 6RY1703-0CA01, the CUD1 immediately controls the new board using its existing field current parameter settings.

Q4: The field supply board was damaged after a motor insulation failure. What should be checked before fitting a replacement?

A motor insulation failure can create a short circuit in the field circuit, potentially overstressing the field supply board. Before fitting a new board, perform an insulation resistance test on the motor field winding. If field winding insulation is compromised, repairing only the board without also addressing the motor fault risks repeat damage.

Q5: Where is the 6RY1703-0CA01 sourced?

SIMOREG DC drive spare parts specialists hold exchange stock for this field supply board. Confirm the component designation (C98043-A7014-L2) on any sourced board matches. Test with a clamp meter after installation to verify the field current is within specification.