
One way to characterize oven ports is by using a thermocouple probe inserted and potted with epoxy into a ferrule – just like when terminating a fiber, except you’ll be inserting the thermocouple tip instead of a fiber.
Cure it, as you would a regular termination, and now you have a temperature probe that mimics your product exactly.
For example, if you pot the thermocouple into an SC connector, now you have a thermocouple probe with an SC connector on one end, and your measurements will indicate the temperature INSIDE the connectors, which is really the temperature we are most concerned with.
Follow these steps:
- Use a 0.9-millimeter (900-micron) diameter thermocouple – or smaller, to ensure the thermocouple tip can fit inside the rear of a ferrule or connector you will use.
- Inject epoxy into the ferrule (or connector), and pot the thermocouple probe in the ferrule, so that the thermocouple tip is bottomed out against the base of the ferrule. (Do this as if you’re making a normal connector with optical fiber. Of course, there will be no fiber or anything within the ferrule bore, just the tip of the thermocouple positioned in the middle of the ferrule assembly.)
- Cure as normal. This will be your temperature probe: a ferrule (or connector) with a thermocouple tip positioned in the center of the ferrule, right where the fiber strip point will be in your product. This is the area you want to ensure reaches your curing temperature set point.
- Place a thermocouple-connector probe into each port of your curing oven. Note how much time is needed for the center of the ferrule to reach the desired curing temperature, what the maximum temperature reached is, and how stable the temperature is throughout the curing time.
- Repeat the above steps to measure the temperature in every port. Since temperatures can vary port-to-port, this process will tell you whether the temperature is consistent across all ports in your curing oven.
- Characterize the oven ports annually, so you can track whether the temperature in all ports has remained stable over the past year. Adjust your curing schedule, or replace the curing oven as necessary.
READ THE BLOG: Bonding Optical Fiber to the Ceramic Ferrule Part 2: Best practices to characterize oven ports used to thermally cure epoxy
Additional resources from the FOC team include:
- Category Resource
- View the Glossary, Acronyms, Military Specifications for Connectors
- Q&A Resource: email technical questions to AskFOC@focenter.com
Have questions about this FOC Tip?
Contact FOC with questions at: (800) 473-4237 / 508-992-6464 or email: FiberOpticCenter@focenter.com and we will respond ASAP.
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