It becomes 1, but it doesn't stay at that value for very long. Do you want to use it as a trigger/gate? Maybe test for an interval of values rather than exactly equal to 1, for example
(1 repeatingTriangle: 5 s) gt: 0.99
or
(1 repeatingTriangle: 5 s) gt: !OnDur
which would let you adjust the fraction of time each cycle is on.