ORIGINAL Excitation Board 6RY1703-0EA02 C98043-A7004-L2 6RY17030EA02 C98043A7004L2 6RY17O3-OEAO2 C98O43-A7OO4-L2

Siemens 6RY1703-0EA02 | SIMOREG DC-MASTER 6RA70 Field Supply Board — C98043-A7004-L2 High-Current Excitation

Market Order Number: 6RY1703-0EA02

Internal Component: C98043-A7004-L2 (variants -8, -9)

Manufacturer: Siemens AG (Germany)

Product Type: Field Supply Board — Excitation Control Board

High-Power Field Excitation

The 6RY1703-0EA02 is the field supply board for large SIMOREG DC-MASTER 6RA70 drives in the 850A–1660A current range. It controls the DC excitation current through the motor's field winding — the magnetic flux that the armature current acts against to produce torque. Without stable, correctly regulated field current, DC motor performance is compromised at every operating point.

At the 850A–1660A drive scale, the field supply board must handle higher power levels than the boards used for smaller drives. The C98043-A7004-L2 is the appropriate field supply assembly for this current range. Smaller drives in the 140A–510A range use C98043-A7014-L2 (market number 6RY1703-0CA01) — a different board not interchangeable with the 6RY1703-0EA02.

Sub-Variants and the -8/-9 Suffix

The C98043-A7004-L2 base board comes in sub-variants, identified by the suffix after the L2 designation — notably L2-8 and L2-9. These suffixes indicate specific production configurations tied to particular power section assemblies within the 850A–1660A range. The 6RY1703-0EA02 market order number encompasses these variants.

When sourcing a replacement, confirm the exact sub-variant from the label of the installed board. Fitting an incorrect sub-variant can result in incorrect field current regulation for that specific power section.

Drive Range and Board Selection

Key Specifications

FAQ

Q1: The SIMOREG shows F038 (field current loss) on a 1200A drive. Is the 6RY1703-0EA02 the likely cause?

F038 with a 1200A drive — which is in the 850A–1660A range served by the C98043-A7004-L2 — points directly to the field supply board. Confirm by measuring actual field current at the motor terminals with a clamp meter. Zero or significantly reduced field current with the drive in run state confirms a board fault.

Q2: Can 6RY1703-0CA01 substitute for 6RY1703-0EA02 if the latter is unavailable?

No. The 0CA01 (C98043-A7014-L2) is designed for 140A–510A drives. The 0EA02 (C98043-A7004-L2) serves the 850A–1660A range. They differ in circuit capacity and thyristor bridge configuration. Fitting the wrong board causes incorrect field current and potential motor damage.

Q3: The field supply board failed after a motor insulation fault. What is the correct repair sequence?

First, test the motor field winding insulation resistance. A winding-to-earth fault in the field circuit creates the overcurrent condition that destroys the field supply board. Repair the motor insulation first, then fit the replacement 6RY1703-0EA02. Fitting the new board without addressing the motor fault causes immediate repeat failure.

Q4: Does replacing the field supply board require CUD1 parameter changes?

No. CUD1 parameters — including field current setpoints and field weakening curves — remain unchanged. The new board takes over field regulation immediately on power-up using the existing parameter settings.

Q5: Where is the discontinued 6RY1703-0EA02 sourced?

SIMOREG DC drive parts specialists and industrial repair companies hold exchange stock. Confirm the C98043-A7004-L2 sub-variant (-8 or -9) from the installed board label before ordering. Request a functional test certificate from any aftermarket supplier.