Unformatted text preview: Remember, if he ties one button down, the other button will not start the machine. You may have to use timers. 4. A boiler has a N.C. high temperature safety switch. When the high temperature safety switch opens, sound a horn with two short blasts and one long blast. (1 second on, 1 second off, 1 second on, 1 second off, 3 seconds on 2 seconds off then repeat the cycle.) Turn the horn off when the temperature switch resets and a N.O. acknowledge pushbutton is pressed. R. Khan Nov. 2009...
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- Fall '10
- 12-hour clock, Push-button, industrial automation, high temperature safety