I will transfer on Beijing Capital Airport T3 to Manila in February 2017.

First of all, the service counters in T3 are located at East & West of public space of Arrival Hall at 2nd foor of T3-C. Hereunder is the detailed fare standards:
For a baggage with length + width + height no more than 65cm:
20 RMB/each baggage Within 24 hours
For a baggage with length + width + height between 65 and 115cm:
30 RMB/each baggage Within 24 hours
For a baggage with length + width + height between 65 and 180cm:
40 RMB/each baggage Within 24 hours
For a baggage with length + width + height more than 180cm:
60 RMB/each baggage Within 24 hours
Hope helpful!