The load is now a boiler. (See Figure 4, page 20.) This wiring diagram shows 120 V coming from L1 of a circuit breaker, through a switch, powering a boiler control and returning through L2, back to ...

To further demonstrate this, Figure 10 shows a three-dimensional view of the Basic Gas Ratio (IEC 60599-2007-05). Figure 10 (click to enlarge) ... These gas concentrations are calculated and then ...