# Measurement Service for Determining Positioning Accuracy on SMT Equipment

## Determining SMT Reflow Oven Temperature Profile Repeatability of

• Determination of the repeatability of temperature profiles
• The following parameters are evaluated:
• Peak Temperature
• Reflow Time
• Soak Time
• Objective and independent measurement and analysis certified according to DIN ISO 9001
• Calculation of $$C_m$$ and $$C_{mk}$$ values based on given specification limits
• Detailed and meaningful test report

### Preparation from CeTaQ

• Measuring system for oven measurement with 8 sensors
• Calibrated glass boards

### Preparation from Customer

• Executable machine program
• Ensuring a good condition of the system to be inspected by prior maintenance
• Technical support for setting up and operating the system
• The oven to be measured must be preheated

### Data Acquisition

The system to be examined is prepared by the technical support and the corresponding program is loaded. The input and output conveyor must be adjusted to the corresponding width. The measuring system passes through the oven like a regular circuit board. The temperature profile is recorded over time at 8 different temperature sensors. These have the same thermal masses in the cross profile. The system must cool down at the end of a run. The process is then repeated. In total, 20 profiles are recorded.

### Analysis of the Results

When the measurement is finished, the data is exported in an ASCII readable format and transformed into CmCStat. Parameters for this are peak temperature, time over liquidus and soak time. For this purpose, the measured values of the thermocouples, which are positioned at the same height transversely to the transport direction are summarized. This means that the cross profile is also included in the evaluation. The nominal values are determined on the basis of a preliminary run through the first 10 attempts. These go into the calculation of the capability characteristics for the evaluation, detailing results of the systems repeatability.

### Report Writing

Based on the final condition reached, a test report is written at the end of the evaluation. This is usually written in our office within a few days after a customer visit. Besides the detailed description of the final results, it contains the history of the necessary steps to reach the final condition.

• The measuring system used is calibrated on the basis of international standards.
• The method is suitable for all reflow ovens whose transport system can handle the measurement shuttle.
• The time required for a complete examination is 6 to 8 hours, depending on the energy input during passage. The decisive factor here is the cooling time and is minimized as much as possible with a special fan driven cooling system.