Description
SPAU140C ABB intermediate relay
SPAU140C is a digital synchronous check relay produced by ABB, belonging to ABB’s medium voltage protection and control product line, originating from Sweden, with document number 1MRS750421-MBG. It should be noted that this product has been discontinued since 2012.
SPAU140C ABB intermediate relay
The core positioning is used for synchronous and voltage checks when two networks are connected in the power system, to prevent damage to equipment caused by asynchronous closing.
In terms of main functions, the first is the synchronization check function. When two independent networks or two electrically interconnected network parts need to be connected, the relay checks whether the amplitude, phase, and frequency difference of the voltage on both sides of the circuit breaker meet the preset conditions. Only when all conditions are met can the circuit be closed. The second is the voltage check function, which checks whether the voltage meets the requirements when the disconnected busbar or line is to be connected to the live part of the network. The third is a dual operation stage design, with two identical operating units built in, which can simultaneously check the closing conditions of two independent circuit breakers. Therefore, it can also be used for dual busbar switchgear. The fourth is two operating modes. In continuous mode, the relay sends a closing permission to the external control module, while in command mode, the relay directly controls the circuit breaker to close through its own output. The fifth is the self diagnostic function, with continuous automatic monitoring of both hardware and software. When there is a fault, an alarm is sent through the indicator light and serial bus.
In terms of key parameters, the auxiliary power supply is 240VAC plus or minus 15 percent, powered by a dedicated power module SPTU240R4. There are also 120VAC North American and 24VDC DC versions available. The voltage input is 100V or 110V phase voltage, selected by dialing. The overvoltage setting range is from 110 percent to 130 percent of the rated voltage, and the undervoltage setting range is from 50 percent to 80 percent of the rated voltage. The adjustable time delay range is 0.1 seconds to 30 seconds. The output contacts consist of 2 normally open trip contacts and 1 signal contact. The communication interface supports Profibus DP bus serial interface, which can connect SPA bus and upper level host system. The protection level of the front panel is IP40, and when installed inside the switchgear, it is IP20. The working temperature ranges from minus 25 degrees Celsius to plus 55 degrees Celsius. Certification complies with IEC 60255, CE, UL standards.
Typical application scenarios include synchronous circuits for generators in thermal power plants and hydropower stations, ensuring that the generators are connected to the grid under appropriate conditions. Safe shutdown of key equipment such as mixers and compressors in chemical and mining scenarios due to abnormal voltage. Verify the voltage quality after the restoration of mains power during the backup power switch in the data center. It is also widely used for feeder protection and distribution automation in substation automation systems.
It should be noted that some suppliers online label SPAU140C as a power control module or DCS controller module, which does not comply with the official ABB document definition. According to ABB’s official product guide, SPAU140C is clearly designated as a synchronous inspection relay. If you are doing project selection or fault replacement, it is recommended to confirm the model based on ABB’s official document 1MRS750421-MBG, while also noting that the product has been discontinued and alternative solutions need to be considered.
