In a simple current loop containing a transmitter, a power supply, a recorder, and a controller, which sequence correctly represents the series connection starting from the power supply positive terminal?

• A. Power supply positive -> Transmitter positive -> Transmitter negative -> Recorder positive -> Recorder negative -> Controller positive -> Controller negative -> Power supply negative
• B. Power supply positive -> Recorder positive -> Recorder negative -> Transmitter positive -> Transmitter negative -> Controller positive -> Controller negative -> Power supply negative
• C. Power supply positive -> Controller positive -> Controller negative -> Transmitter positive -> Transmitter negative -> Recorder positive -> Recorder negative -> Power supply negative
• D. Power supply positive -> Transmitter positive -> Recorder positive -> Controller positive -> Controller negative -> Recorder negative -> Transmitter negative -> Power supply negative

Answer: (C)

In a current loop, all devices are wired in one continuous path so the same current flows through transmitter, recorder, and controller. The critical idea is that from the power supply positive, the current must enter the next device at its positive terminal and exit at its negative terminal, continuing to the next device, and finally returning to the power supply negative.

The sequence that starts at the power supply positive and then moves through the controller, then the transmitter, then the recorder, and back to the power supply negative maintains a clean, single path where each device receives current through its positive terminal and passes it on through its negative terminal. This forms a proper series loop with correct polarity for every element, ensuring the current can flow through all devices uninterrupted.

Other arrangements would either break the single-path flow or connect like-polarity terminals together, which does not preserve the required series current path.