Control system regulator in forward mode, reverse mode, forward output, reverse output

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For the AO point configuration, there are options for positive and negative output; in my understanding, the positive output corresponds to air-operated open valves with a 4-20mA signal, while the negative output is used for air-operated closed valves. In the 20-4ma monitoring screen, the adjustment screen shows the positive and negative effects of the regulator. In my understanding, when the liquid level measurement is higher than the set value, it is necessary to reduce the valve opening, and a reverse action should be selected. For example, the control valve at the container feed inlet. When the liquid level measurement is above the set value and an increased valve opening is required, a direct-acting type should be chosen, such as the control valve at the container’s discharge outlet. Is this understanding correct? Could the experts please offer some advice?