Library /sys$common/syshlp/ncphelp.hlb SET, CIRCUIT, ACTIVE INCREMENT increment  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Applies to DDCMP CONTROL circuits. This parameter indicates the
 increment value added to the ACTIVE tributary priority each time
 the scheduling timer expires.  The increment value must be a
 decimal integer from 0 to 255.  The ACTIVE INCREMENT default is 0.