Resistor identification

[cpposteve]

Hi all. Trying to identify this resistor and having a hard time as it doesn’t follow conventional colour coding specs. Pic attached. It’s on the mains incoming on a pcb. I’m hazarding a guess at it being 7.5 ohms but if someone could clarify and explain the banding on this I would be great full.

Thanks

Steve

[coromonadalix]

https://www.hobby-hour.com/electronics/resistorcalculator.php

wich gives 7.5 ohms at 5% tolerance

normally you calculate it as a 4 band colors resistor,  the black is used as a temperature coefficient ??


Just probe it with a meter to confirm its value and match the website deciphered colors

[madires]

7.5 Ohms should be correct. The black ring is most likely an indicator for a fusible resistor. There is no common rule for fusible resistors. Some have an additional ring and the ring color depends on the manufacturer (so far I've seen black, white and green).

[isometrik]

The black ring is most likely an indicator for a fusible resistor.

The RF1 reference designator also seems to imply a "R"esitors "F"usible.

[bob91343]

The background color says fusible.  Those are usually a sort of rough light gray.  I agree it is 7.5 Ohms.

[gamalot]

7.5 Ohms should be correct. The black ring is most likely an indicator for a fusible resistor. There is no common rule for fusible resistors. Some have an additional ring and the ring color depends on the manufacturer (so far I've seen black, white and green).

I have only seen black, white and green additional color rings, I am curious if there are any other colors.