Yes it is fine. This combination of PCB finish and solder alloy is fairly common. 

The process temperature does not need to change from your normal tin/lead bath temperature. You are soldering to the PCB finish you do not melt it. ( think of ENIG )

Unless you have a very small pot and lots of pcbs (with few actual joints) contamination with silver should not be a problem. As has been said most lead free HASL PCBs do not use SAC, it is too expensive. If you are worried do your assay more frequently. 

Regards
Rex

Sent by me on my iPhone. 


On 17 May 2012, at 13:09, "Juliano Ribeiro" <[log in to unmask]> wrote:

> Hi to all,
> 
> Is it possible we use PCB with finishing HASL (Lead Free) in our Tin Lead Process - Solder Wave?
> We need modify some parameters how the temperature?        
> 
> Thank you a lote
> 
> 
> Juliano Ribeiro
> Coordenador de Produção - Placas Eletrônicas 
> Elo Sistemas Eletrônicos S.A.
> Fone: (51) 2131 2217    Fax: (51) 2131 2200
> Cel: (51) 9356 2844                                                                                                                                                                 
> http://www.elonet.com.br 
>  "Antes de imprimir pense na sua responsabilidade com o meio ambiente."
>   Adote os 4 R´s (Reduzir, Reutilizar, Repensar e Reciclar)!
> 
> 
> ______________________________________________________________________
> This email has been scanned by the Symantec Email Security.cloud service.
> For more information please contact helpdesk at x2960 or [log in to unmask] 
> ______________________________________________________________________
> 
> ______________________________________________________________________
> This email has been scanned by the MessageLabs Email

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________