Final answer:
To set the low-pressure switch to cut out at 30 psig, you would need to adjust the cut-in setting or the differential depending on the current settings, which the question does not provide. Without knowing the cut-in and differential settings, a definitive action cannot be recommended.
Step-by-step explanation:
The question pertains to setting the parameters of a low-pressure switch in a system where gas volume and pressure are related. The low-pressure switch has two main settings: the cut-in and the cut-out point, as well as a differential setting, which is the difference in pressure between the cut-in and cut-out points. According to the instructions 'cut-out is cut-in less differential', which means the cut-out value is obtained by subtracting the differential from the cut-in pressure. To achieve a cut-out pressure of 30 psig, you need to adjust the cut-in or differential settings accordingly.
- If the current cut-in setting is above 30 psig and the differential setting is fixed, the cut-in setting would have to be decreased to reach a cut-out of 30 psig.
- If the cut-in setting is already at or below 30 psig, then the differential would need to be increased. However, there must be caution as increasing the differential beyond a certain point could also increase the cut-in beyond desired levels.
It is important to note that the actual approach depends on the current settings of the low-pressure switch. Without knowledge of the current cut-in and differential settings, a definitive action cannot be recommended. Moreover, the scenario of the gas volume and pressure in the cylinder illustrates the principles of Boyle's Law, where pressure and volume are inversely proportional.