EXFO FTB-2 Guide De L'utilisateur page 503

Error
Description
Number
–700 "Request control"
–800 "Operation complete"
FTB-2/FTB-2 Pro and FTB-4 Pro
Probable Cause
[The instrument requested to become the active
IEEE 488.1 controller-in-charge.]
[The instrument has completed all selected
pending operations in accordance with the IEEE
488.2, 12.5.2 synchronization protocol.]
SCPI-Based Errors
487