Electrical faults are hard to trace, usually because there are no records and no backups. This section is about bringing a control system to the point where a problem can be investigated and a failure can be recovered.
Each guide is organised in three parts — daily care points, periodic maintenance table, common mistakes — so you can put it to use as is.
The PLC itself is reliable. What actually causes trouble is three things: no programme backup, poor power quality and messy earthing. All three are management problems, not technical ones.
VFD failures have a very narrow set of causes: poor cooling accounts for over half, and most of the rest are wrong parameters or supply problems. With proper care, service life goes from three to five years to over eight.
Motor burn-out and welded contacts both give warning signs beforehand. The value of periodic testing is turning those signs into planned maintenance shutdowns instead of unplanned production incidents.
Annual electrical cabinet maintenance does not take long, but it does need a power-down window. Prepare the checklist in advance and finish within the day — do not spend the window hunting through documentation.
Electrical faults are defined by small triggers and big losses: one communication cable with a poorly connected shield can make an entire automated line stop at random, and one electrical cabinet with a blocked cooling airflow can blow a drive module worth tens of thousands of yuan in summer. Moreover, electrical faults are mostly intermittent and compound, and the cost of investigating afterwards far exceeds the cost of preventing beforehand.
The care logic for this category is "environment first, backups as the backstop, data speaking": once the environmental problems - dust, temperature rise, moisture - are treated, electrical faults drop by more than half; with programs and parameters backed up, fault recovery shrinks from days to hours; with trend data recorded, even intermittent faults can be captured and attributed. The four articles cover daily PLC care, VFDs, motors and low-voltage electrics, and the annual electrical-cabinet service.
FIELD · SCHH-2026
FIELD · SCHH-2026
FIELD · SCHH-2026Because most plants' backups are unusable: the version does not match the program running on site, backup files are corrupted and nobody ever verified them, or the storage media are lost. A sound backup system has three elements: back up immediately after every change, verify backups periodically by restoring them, and keep two copies in separate locations. When we deliver the management system, we write these three rules into your procedures and assist with the first full backup and its verification.
It depends on the equipment: high-voltage gear and main transformers must undergo withstand-voltage and insulation tests at the intervals required by code - that is mandatory. Low-voltage systems need at least an annual insulation megger test, ground-resistance measurement and protection-trip test. The cost of electrical testing compares favorably with outage losses: insulation degradation follows a clear deterioration curve in the data, and testing is how you plot that curve so replacements can be scheduled before breakdown.
This section was written in-house by the Industrial Equipment Services Division. Thresholds and intervals are field-experience values; in practice follow the equipment manufacturer's technical documents and current national standards.
Send us your equipment list and we will specify inspection items, intervals and acceptance criteria for your operating conditions.
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Guangzhou Yujihang Computer Technology Co., Ltd. · www.accpc.com.cn
Guangzhou Henghuan Technology Co., Ltd. · www.hhrobotics.cn
Nanchong Henghuan Robotics Co., Ltd. · www.hhrobots.cn