Rexroth Indramat 109-0780-4A01-02 Hall/Tacho Servo Circuit Board

Description

Product Introduction

The Rexroth Indramat 109-0780-4A01-02 (also referenced under the TKF3 family designation) is a specialized feedback processing circuit board installed within legacy Indramat AC servo motor drive architectures. It handles real-time speed acquisition and rotor position verification by conditioning signals sent directly from internal tachogenerators and Hall effect sensors. Built specifically for high-torque industrial motion control applications, this board converts raw analog feedback into clean signals required by the drive controller to maintain precise velocity loops.

Unlike modern digital absolute encoder interfaces, the 109-0780-4A01-02 relies on robust, low-latency analog filtering circuits designed to resist heavy electrical noise in harsh factory environments. It serves as a drop-in replacement card for older MAC series motor feedback assemblies, maintaining tight speed regulation without requiring expensive complete motor retrofits.

Key Technical Specifications

Application Scenarios & The “Trench” Experience

The Trench Story: It’s 2:15 AM on a Tuesday. An automotive stamping line trips with a velocity feedback error (F208/F209 drive fault). The line is down, costing $12,000 an hour. The technician swaps the drive, but the fault remains—the problem is inside the motor end-bell. The internal 109-0780-4A01-02 feedback card took a power surge through the shield ground, blowing out the analog trace for the tachometer signal. Rather than pulling a 400 lb motor and waiting six weeks for a custom rewind, the shift engineer pops open the end-cap, replaces the burnt 109-0780 board, clears the fault, and gets the line running before sunrise.

Application Scenarios:

• Automotive Body Stamping: MAC motor speed feedback on heavy transfer presses requiring precise, high-torque positioning under sudden impact loads.
• CNC Gantry Milling Machines: Velocity loop processing on legacy axis drives where ripple-free analog speed control prevents tool chatter marks.
• Printing & Converting Lines: Real-time web tension control where analog tachometer feedback prevents web breakage during rapid acceleration.
• Metal Processing & Cut-to-Length Lines: Synchronized feed rolls relying on Hall sensor timing to dictate precise shear cutoff locations.

109-0780-4A01-02

109-0780-4A01-02

109-0780-4A01-02

109-0780-4A01-02

Transparency SOP: Quality Assurance & Testing

We do not just ship boxes; we test them on actual Indramat drive setups. Every 109-0780-4A01-02 board undergoes a strict 5-step validation before leaving our warehouse:

1. Inbound Inspection: Multi-point visual check under magnification to detect component charring, cold solder joints, trace degradation, or cracked SMD components.
2. Live Rig Testing: Installed into a live Indramat drive test bench paired with a functional MAC servo motor.
3. Signal Waveform Verification: Oscilloscope validation of both raw tachometer input signals and conditioned outputs across the full RPM curve.
4. Thermal Stress Testing: Run under load inside an environmental test chamber to detect intermittent thermal failures.
5. Final QC & ESD Packaging: Sealed in anti-static, moisture-barrier packaging with a verified test tag logging individual component values.

The Veteran’s Tech Trap Guide

⚠️ Watch out for suffix revs! A 109-0780-4A01-01 and a 109-0780-4A01-02 look identical at first glance, but revision changes often update onboard resistor values for specific motor winding impedances. Double-check your exact part suffix before swapping cards.

❗ Grounding matters. 90% of the blown operational amplifiers on these boards stem from improper motor cable shielding. If your motor’s ground strap corrodes, the tachometer feedback return becomes the path of least resistance for high-frequency PWM noise, frying the board.

⚠️ DIP switch configuration: Take a high-resolution photo of the board’s jumpers and DIP switches before unhooking the old card. Trust me on this—matching gain and offset settings out of the box will save you two hours of oscilloscope tuning on the factory floor.

❗ ESD Risk: These vintage boards lack modern ESD suppression diodes on the signal inputs. Touch the grounded motor housing before handling the board. Handling this card bare-handed on a synthetic shop floor will static-zap the sensitive ICs faster than you can say “fault code.”

Frequently Asked Questions

Q: Can I hot-swap the 109-0780-4A01-02 board while the drive is powered up?

A: Absolutely not. Pulling or inserting this card under power will arc the feedback pins and permanently damage both the card logic and the drive’s main control card. Discharge the DC bus fully before touching the assembly.

Q: Is the 109-0780-4A01-02 interchangeable with the 109-0780-4B01-02?

A: In most cases, yes, the 4B iteration is a factory-revised replacement for the 4A series. However, you must verify signal voltage levels with your motor manual, as scaling parameters can vary slightly depending on the motor frame size.

Q: Do I need to recalibrate the drive after installing this board?

A: Yes. Because this is an analog speed control board, minor component tolerances mean you will likely need to adjust the drift and gain pots on your drive to eliminate zero-speed crawl or overshoot.

Q: What is the warranty on these legacy surplus/refurbished boards?

A: Every unit comes backed by a standard 12-month operational warranty covering functional component failures, giving you factory-level confidence without the OEM lead times.

Q: Why is your surplus pricing lower than ordering directly through legacy OEM channels?

A: We source surplus inventory globally directly from plant modernizations, decommissioned facilities, and overstock inventories. You get original, tested OEM hardware without paying current OEM legacy penalty markups.