Does the input terminal specifically refer to the analog pressure value that needs to be input before the sensing element?

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The coal chemical industry construction standards specify the following requirements for detection circuits: First, the signal input terminal of the detection circuit must receive a standard signal representing the variable being measured. Second, in temperature detection circuits, the output terminal of the sensing element can supply either a resistance value or a millivolt standard signal to the circuit. Third, in cases where it is not possible to have a circuit that can simulate the variable being measured, tests should be conducted by introducing the signal at the very beginning of the circuit, where an analog input signal can be applied. At the time of settlement, a problem arose. Regarding the first item, the signal input end of the testing circuit was used to simulate the standard signals of the variable being measured. The client insisted that what was fed in were pressure-based simulation signals generated through devices such as pressure testing pumps; whereas, it is common practice in construction to apply signals at the output end of the measuring instruments (that is, by using 4-20mA current signals via cables). As a result, the client concluded that the testing circuits for parameters such as pressure did not comply with the specifications for circuit testing, and submitted this conclusion to their financial control department. I would like to ask the more experienced colleagues: does the input terminal specified in this first specification indeed refer to the analog pressure value that needs to be input before the sensing element?