See the following console session

% interp create slave
slave
% set cmdlimit [slave eval {info cmdcount}]
280
% slave limit command -value [incr cmdlimit 5]
% slave limit time -seconds 600
% slave eval [list expr 1+3]

% set errorInfo

    while executing
"expr 1+3"
    invoked from within
"slave eval [list expr 1+3]"
    ("uplevel" body line 1)
    invoked from within
"uplevel #0 {slave eval [list expr 1+3]}"
% set errorCode
NONE

The time limit is in the past (it was actually a programming error, should have been absolute time, not relative). An error was generated as expected. However the error message is empty and error code is NONE (expected to be TCL LIMIT) resulting in my trap handler not firing.