Compliance logo?

I don't recognise it but it will be the blank pcb manufacturers logo and it will be registered with UL.

Often there will be a number starting with E as well which is the UL file number. You can look this up on the UL website.

pcb

posistion

blocker

Thanks for that, there is an E...... number there, I'll look up

Check it here:

It will give you full details of their UL approvals. For example they may be certified for double sided but not multilayer.

It will give you the company name and location as well.

Maybe

So from the E number RUIHUA PRINTED CIRCUIT BOARD CO FUZHOU, FUJIAN, CHINA and under that number on this pcb is from the UL info the pcb sub-class type

I was hoping the symbol was for indicating that it was suitable for PbF solder use but is probably the logo for that company, although I've not found a company site with logo on it

They make 23 subclasses of board involving 3 solder limit types

Yea, that?s the Company Logo. Standard practice for a UL certified product is to have the MFG Name or logo, UL file number, and mfg date etched in either the top or bottom layer of all the boards in the product. You may even see 94-V0 (flame rating for FR4) some where there too.

As for PBF, there are a few plating choices. Lead Free HASL, Immersion Tin , Immersion silver, ENIG, and Gold plate ( over nickel) Sunstone has a nice comparison list.

Cheers

...that is "UR", not "RU"...Underwriters Registered.

All I've found so far on temp-dwell time comparison and PbF is

I'm thinking the 270 deg C - 10 sec criteria is more demanding than the 288 dec C/8 sec dwell ,as more heat in joules is involved, rather than the higher temperature

You must be looking at the wrong side of the board.

...and it indicates a "UL Recognized Component".

Best regards, Spehro Pefhany