A fingerprint stops a link
A new fibre link tests perfectly on Monday. On Friday a technician unplugs it to look inside, touches the end with a thumb and plugs it back.
The link now drops out every few minutes. A thumb print on a glass end, thinner than a hair, is enough. Much of the loss in fibre comes from handling.
Key words
| Word | What it means |
|---|---|
| Contaminated | covered with dust, oil or dirt |
| Ferrule | the small ceramic tube at the tip of a connector that holds the fibre |
| Dust cap | a cover that keeps a fibre end clean |
| Bend radius | how tight a curve a cable can take without harm |
| Tension | a pulling force on a cable |
| Intermittent | a fault that comes and goes |
| Attenuation | the loss of signal strength as it travels |
| Reflection | light bouncing back along the fibre at a poor join |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can say how dirty connectors, bends and poor parts cause signal loss, and how to avoid each.
Starter: causes of loss
Have a go
Starter: causes of loss
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Dirty, faulty or contaminated connectors
The core of a fibre is tiny. A speck of dust can cover it. Finger oil smears across the end. A scratch or crack in the ferrule scatters the light.
A dirty end can give an unreliable link that comes and goes. A very dirty or damaged one gives no connection at all.
Caring for a connector
| Do | Do not |
|---|---|
| Keep the dust cap on until the moment of use | Leave an end uncapped on the floor |
| Inspect the end with a viewer first | Look straight into a live end |
| Clean with a proper wipe or click cleaner | Wipe on a sleeve or a shirt |
| Inspect again after cleaning | Assume it is clean |
| Replace a scratched or cracked connector | Keep using it |
The cells students fill in are left blank in this preview.
Put the care steps in order
Have a go
Put the care steps in order
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.