NF DP420LS Instruction Manual page 119

4. Advanced Operation
3. You can select s or ms as the unit of Step Time by selecting [Misc] soft-key  [1: TimeUnit].
4. You can set polarity of trigger output and pulse width by selecting [Misc] soft-key  [2: Trig
Out].
5. Press the [Clear] soft-key to clear all the steps you are editing and return to the factory default.
100 PROGRAMMABLE AC POWER SOURCE