Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


%RH in the Production Hall

Views: 1366

Steve H.

#42736

%RH in the Production Hall | 17 July, 2006

Hi,

I was wondering, if there were any guidelines to what %RH the production hall should be running within, and what consequences can occurr, if we are running higher or lower than the reccommendations.

I am worried, with regards to the above, as we are currently running at approx 55-58%RH, and we have recently seen an increase in Solder Bridges and skips, is this related ??

Best Regards

Steve

reply »

Chunks

#42743

%RH in the Production Hall | 17 July, 2006

Never seen a direct study on these two correlation�s before. But if you have moisture sensitive devices, higher humidity could have some affect on them. If you are talking regular Rs and Cs over wave solder - I kinda doubt it. Water based fluxes do cause a violent reaction over the wave if not properly evaporated. When this happens, you can hear it sizzling. Do you hear any sizzling at the wave?

If you're talking reflow soldering, I seriously doubt 55% humidity could have an affect on reflow.

Production Hall? Never heard it called that before.

reply »

SWAG

#42744

%RH in the Production Hall | 17 July, 2006

Lower RH = more static build-up on production floor = greater chance of ESD damage to product. Primarily, I think your SMT print job can be affected by RH which could cause defects like the ones you mention. Look at ANSI/ESD S20.20 for more info and recomended, acceptible RH ranges. I think a range of 30-70 percent is considered acceptible but you should look it up for sure.

reply »

#42750

%RH in the Production Hall | 17 July, 2006

Hello there, I'd love to have HR at 50-55%, but also temp at 21-23 deg C, with hot start of summer in Poland, we have on prod.floor close to 30 deg C and 30%HR, it is really difficult to print properly and to get pcb through oven without problems... last wednesday we went to 32 deg C and lots of bridges formed... I'm really waiting for new clima instalation...

reply »

#42757

%RH in the Production Hall | 17 July, 2006

SWAG

#42768

%RH in the Production Hall | 18 July, 2006

We run humidifiers in our shop because we are usually around 25% RH. We track this with a data-logger and RH device. It's dry here! Sometimes in the summer, it can get between 5 and 10% RH outside = thunderstorms/dry lightning and forest fires. I think the biggest concern for us in the shop is static build-up that occurs easily at low RH.

reply »

Plasma Prior to Conformal Coating

Heller Industries Mark 5获得了 2015年中国SMT远见奖 - 回焊炉领域