What is the frequency conversion signal type of the pump?

The type of signal output depends on what type of explosion-proof certification the device that generates the signal holds. Current DCS cabinets are all installed in cabinet rooms (safe areas), and therefore do not have explosion-proof certification. Therefore, its signal cannot be considered intrinsically safe nor explosion-proof. The DCS cabinet is located in the safe area, and the MCC electrical cabinet that receives the AO frequency conversion signals from the DCS is also situated in the safe area. Therefore, there is no need to consider the explosion-proof type of this signal. If an isolation barrier is indeed used, it is actually employed merely as an isolator, taking advantage of its isolation function; this approach does not involve using it as a safety barrier. As for installing isolators on this signal line, it is done to prevent the influence of electrical signals from two different systems; it has nothing to do with explosion protection. As for what you asked, whether it’s a safety barrier or an isolation barrier. This question is wrong in itself; an isolation barrier is a type of safety barrier. Safety barriers are generally divided into Zener barriers and isolation barriers.