According documentaion for S93:
"The main control units of the SRU work in 1+1 backup mode. The data switching units can work in either 1+1 load balancing mode or 1:1 backup mode"
Question is how to configure 1+1 or 1:1 mode for SRU ?
After consultation with RnD have confirmed that current documenation is not clear. We should consider that 1:1 backup mode it is for control plane: if one SRU is pull out/damage then second SRU will take loading and provide non-stop work of S93 switch. 1+1 balance mode mean that switch will share resource of second SRU if it is need automatically (for example when need provide switching between 48GE and 10G boards need install two SRUA type board) , such behavior can not be configured from command line and such function provided at hardware level.
Documentation don't have any reference about how to configure 1+1 or 1:1 mode.