1.Hitachi CMI563 SRP-4 Probe Overview

1. Overview of the Hitachi CMI563 SRP-4 Probe

The Hitachi CMI563 Probe, specifically the SRP-4 measurement probe variant, is a specialized sensor engineered for the Non-Destructive Testing (NDT) of copper layers on printed circuit boards. Unlike traditional eddy-current probes that may be affected by the substrate material or the copper on the opposite side of a board, the SRP-4 utilizes a Four-Point Probe method.

This tethered probe features a patented design with four securely encased pins. Its see-through casing allows for precise placement on small traces, making it an essential tool for PCB Quality Control (QC). Whether you are measuring Electroless Copper or Electrodeposited Copper, the SRP-4 ensures that your readings are consistent and reliable.

2. Core Features and Technology

Micro-Resistance Measurement

At the heart of the Hitachi SRP Probe is advanced micro-resistance technology. The probe operates by passing a constant current between the two outer pins while measuring the voltage drop between the two inner pins. This 4-wire Kelvin technique eliminates the impact of contact resistance, allowing for High Resolution Thickness data even on very thin foils.

Key Specifications:

Substrate Independent: The measurement is unaffected by the laminate thickness or the presence of copper on the backside of the board.
Accuracy: Delivers a high accuracy of ±1% (±0.1 μm) relative to standard reference plates.
Versatility: Capable of measuring Copper Trace Thickness on fine lines as narrow as 8 mils (203 μm).
Durability: Features a rugged design with user-replaceable tips, significantly extending the SRP-4 probe lifetime.

3. Applications in Electronics Manufacturing

The Printed Circuit Board Testing environment demands tools that can handle a variety of materials and board configurations. The Hitachi CMI563 SRP-4 Probe excels in several critical areas:

PCB Manufacturing and Assembly: Ideal for inspecting single-sided, double-sided, or multi-layer rigid and flexible boards.
Surface Copper Thickness: Essential for verifying that Surface Copper Thickness meets design specifications after plating or etching.
Incoming Inspection: Companies often use a Used SRP-4 probe or new units to verify the quality of raw laminates from suppliers.
Chemical vs. Electroplating: The gauge and probe are user-selectable for different copper types, including electroless copper (0.25 μm – 12.7 μm) and electrolytic copper (2.5 μm – 152 μm).

4. Probe Data Characteristics and Calibration

Reliable data starts with proper Copper Thickness Calibration. The CMI563 SRP-4 Probe comes factory-calibrated but supports user-defined calibration using NIST-traceable check standards.

Data Precision:

Electroless Cu: Typical precision of 0.2%.
Electrodeposited Cu: Typical precision of 0.5%.
Resolution: Provides readings down to 0.01 mils or 0.1 μm, ensuring that even minute deviations are captured during Electronics Manufacturing audits.

5. Maintenance, Troubleshooting, and Support

To maintain the performance of your Hitachi coating thickness probe, regular maintenance is required.

Troubleshooting SRP-4 Probe

If you encounter inconsistent readings, refer to the SRP-4 operation manual for micro-resistance gauge troubleshooting. Common issues often stem from worn tips. Because the SRP-4 probe tips are replaceable, you don’t need to replace the entire assembly. A Hitachi SRP-4 Probe replacement tip kit is a cost-effective way to restore accuracy.

Hitachi Probe Maintenance Tips:

Clean the Pins: Ensure the four pins are free from oxidation or debris.
Calibration Checks: Perform regular SRP-4 probe calibration using certified standards.
Visual Inspection: Use the see-through casing to check for bent or recessed pins.