Question 475Steam Plants - Assistant Engineer70% to pass
During unsafe firing conditions in a large automatic auxiliary boiler, various control actuators are interlocked with the burner circuit to prevent start-up, in addition to safety shutdown. These controls are referred to as _______________.
AI Explanation
The correct answer is A) limit controls.
Limit controls are safety devices that are interlocked with the burner circuit to prevent start-up and initiate a safety shutdown in the event of unsafe firing conditions in a large automatic auxiliary boiler. These limit controls, such as high pressure, high temperature, and low water level switches, are designed to interrupt the burner circuit and shut down the boiler before dangerous conditions can develop.
The other options are incorrect because:
B) Flame safeguard controls monitor the presence of a flame, but do not necessarily prevent start-up under unsafe conditions.
C) Combustion controls regulate the air-fuel ratio, but do not directly shut down the boiler.
D) Programming controls are related to the automated sequencing of the boiler, but do not specifically address safety interlocks.
Related Questions
#473 The primary function of a flame safeguard system, as used on an automatically fired auxiliary boiler, is to prevent _______________.#474 Constant capacity, pressure atomizing, fuel burners designed to meet a wide variation in steaming loads on an auxiliary boiler, are _______________.#476 One factor for determining the minimum feed water inlet temperature to a boiler economizer is the _______________.#477 If there is a sudden drop in the outlet temperature of an uncontrolled superheater, you should _______________.#478 To safely decrease the boiler firing rate, you should always reduce the fuel pressure _______________.