Isolator Key Selection Considerations
1. Common-mode interference suppression capability: a prerequisite for the advantages of isolators.
Isolator Within the exclusive industry scope, whether it is Temperature Isolation Transmitter 、 Signal distributor 、 Isolation Distribution Unit and Current and voltage transmitters In such products, a common characteristic is the requirement for absolute electrical isolation between ports—meaning there must be no electrical connection whatsoever among primary instruments, power supplies, and data acquisition equipment—and a specified isolation withstand voltage range. This capability addresses the so-called ground potential difference between devices (i.e., common-mode interference suppression). Even the most basic isolation device must have a port-to-port withstand voltage of 1,500 to 2,000 V with a leakage current of less than 1 mA to meet the requirements of numerous industrial applications in China. In certain high-electric-field environments or in aerospace and spaceflight measurement and control applications, the requirements are even more stringent. Paragon ( Nanjing Parokon Technology Co., Ltd. The PA and PR series products from ) boast a unique advantage in this regard: they abandon traditional isolation methods in favor of EMI-based solutions, with some models achieving breakdown voltages exceeding 5,000 V and having been successfully integrated into the supply chains of several overseas manufacturers.

2. Product operating current and power loss during operation.
In today’s society, energy conservation and environmental protection have become the mainstream principle advocated across all industries, with household appliances standing out in particular as a key benchmark for evaluating product quality. However, the instrumentation industry has not yet fully embraced this trend; most instruments typically consume only a few to several dozen watts, so energy efficiency is not a central focus. Nevertheless, even seemingly minor energy losses can have significant adverse effects on the service life and operational stability of instrumentation. Isolators, owing to their specialized function, are designed to enhance I/O modules in industrial settings. In harsh industrial environments such as cement production, environmental protection, and metallurgy, dedicated isolation cabinets are often incorporated during system integration to ensure reliable acquisition and control of field instrument signals. In such cabinets, dozens or even hundreds of isolator products are densely installed. While the temperature difference may be negligible when a single unit operates independently, it becomes markedly pronounced when ten or a hundred units are deployed simultaneously. Experimental evidence has demonstrated:
●1 unit with a power consumption of 40 mA Isolator At a temperature of 25°C, the measured temperature inside a 1 m³ cabinet was 28.7°C;
●When 10 units are densely installed, the temperature is 35.4°C;
●When 100 units are densely installed, the temperature is 52.6°C;
It is evident that the product temperature and quantity are in a multiplicative relationship.
At this point, the issue is no longer merely excessive current draw; it directly affects product lifespan and parameter stability—this is one of the reasons many manufacturers impose specific installation requirements. So how can this problem be solved? There are numerous approaches (such as increasing installation space or adding heat-dissipation components), but these address only the symptoms rather than the root cause. The key to a high-quality product lies in low-loss design from the outset. After all, for any electronic device, the lifespan of internal components is highly dependent on temperature—for example, the service life of a capacitor roughly halves for every 15°C to 20°C rise in operating temperature.
Our goal is to minimize product wastage and losses. The quiescent current of each channel is kept below 25 mA, and thanks to our proprietary isolation scheme, the product maintains exceptional stability across a wide temperature range of –25°C to 85°C. (Test results show that over this temperature range, the full-scale output variation remains ≤1‰ of full scale.)

3. Product Transmission Accuracy
To ensure the accuracy of on-site signal transmission, an isolation device must meet a series of stringent requirements, beginning with its ability to suppress common-mode interference. Common-mode interference refers to extraneous signals that are superimposed onto the transmitted signal due to external disturbance sources during transmission. When such interference is severe, it can cause equipment malfunctions and result in inaccurate data acquisition and control. Given the unique characteristics of industrial environments, it is often difficult to effectively shield against or eliminate these interference sources; therefore, isolation products are required to address this challenge. In the case of thermocouple and small-signal processing, in addition to implementing noise-reduction and filtering techniques, it is essential to employ high-precision, highly stable differential circuits.
In addition, to ensure the overall signal transmission accuracy for isolation products, stringent requirements must be met regarding the products’ inherent conversion and transmission accuracy, encompassing factors such as product stability, susceptibility to external interference, sensitivity to ambient temperature variations, and signal resolution.
In summary, when deploying such products, it is essential to take a comprehensive, multi-faceted approach and ensure that substandard isolation solutions do not become the weakest link in your extensive system.