Abstract: To address the insufficient confidence of static carbon footprint accounting in power equipment manufacturing, a dynamic accounting and uncertainty quantification model based on electricity-carbon integrated metering is established. A compensation model for current transformer (CT) ratio and phase errors under low-load and harmonic conditions is constructed, the Shapley value method is introduced to allocate carbon flows of shared equipment, and the data quality indicator (DQI) matrix is integrated with Sobol variance decomposition to quantify uncertainty propagation. A case study on a 10 000 kVA oil-immersed transformer shows that the dynamic carbon footprint is 38.35 tCO2e, 4.7% higher than the static baseline, with a 95% confidence interval of 35.58, 41.52 tCO2e. The embodied carbon of silicon steel sheets and the regional grid emission factor are identified as the dominant carbon reduction levers. The model reveals the integral amplification effect of metering errors under prolonged low-load conditions, providing quantitative support for refined energy efficiency management in power equipment manufacturing.