Change the Set Value (S.V,) of the Counter #n to value. This statement to allow the user to modify the S.V. of the PLC internal  counters without changing the source program. A TBASIC function can be written easily to make use of a few digital or analog inputs to modify the SV of these internals timers/counters. The new S.V is also stored in the program EEPROM and hence is non-volatile. (See sample program "set_TCSV.PC4")

n should be between 1 and 128.
value should be between 0 and 9999.

Counter #10 will assume a S.V. of 1234..
S.V of Counter #3 will be increased by 10.

Related : The present values (P.V.) of counters can be read or written directly as integer variables   "CtrPV[n]". But the Set Values can only be changed by this function.