About the AC-410 Phase Sequence Loss Monitor from the ATC Diversified Electronics division of Marsh Bellofram: This internal control relay drops out and a 3 minute delay-on-break time delay begins. This delay is used to lock out the compressor, allowing time for head pressure to equalize. When the delay has completed, the relay will re-energize provided all conditions are corrected and the external control voltage is present on terminals six (6) and seven (7). A green indicator glows when all line conditions are normal and a red indicator shows when the timer is in its delay.