> what is the current carrying capacity of 25mm multicore armoured thermoplastic insulated cables with aluminium conductors, on perforated cable tray?

  This is an electrical engineering question rather than a software engineering one, but let me look it up for you.

  WEB SEARCH ("current carrying capacity 25mm multicore armoured thermoplastic insulated cable aluminium conductors perforated cable tray BS 7671")
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   Based on BS 7671 Table 4D4B (multicore armoured thermoplastic insulated cables with aluminium conductors), the current-carrying capacity for a 25mm cable on a perforated cable tray (Reference Method E) is approximately 80A for a 3- or 4-core cable at 30C ambient temperature and 70C conductor operating temperature.

    Note: The exact value depends on the number of cores (2-core vs 3/4-core) and whether any rating/correction factors (grouping, ambient temperature, thermal insulation) apply. I'd recommend confirming against the actual BS 7671:2018 Table 4D4B for your specific configuration, as the aluminium conductor ratings are lower than the copper equivalents (~102A for copper in the same conditions).

    This is outside my core domain of software engineering -- for critical electrical installations, always verify with the relevant standards documentation or a qualified electrical engineer.