为了准确评估其对冷负荷的影响，有必要测量建筑物内设备的热损失。建筑设计的最新进展，以及隔热材料和建筑围护结构系统热特性的改善，显著降低了外部来源的冷负荷；然而，在建筑物中增加各种类型的办公室、实验室和医院设备已成为内部冷负荷的主要来源。不幸的是，目前的手册中缺乏关于设备总热增益的准确信息。 一些设备包括显示总功耗的铭牌额定值，而其他设备则没有。一些制造商测量设备的最大耗电量，并将其作为额定功率列在铭牌或设备文献中，而另一些制造商则列出系统的最大功率容量。由于制造商的额定功率（如果报告）通常基于设备在最大容量下工作时的瞬时测量，因此使用设备铭牌值计算冷负荷可能会导致空调设备尺寸过大，从而导致额外的初始成本和更高的运行成本。 另一方面，低估冷却负荷可能会导致冷却能力不足。影响冷负荷计算的另一个因素是来自设备的辐射热负荷和对流热负荷之间的分配。从设备传递到周围环境的热量的对流部分是瞬时负荷，因为它通过自然或强制对流无延迟地添加到室内空气中，而辐射部分被房间表面吸收，然后随时间消散。准确确定冷负荷对于正确确定空调设备的尺寸非常重要。 本文介绍了办公室、医院和实验室设备的总热增益和辐射/对流分离的实验结果。比较和讨论了铭牌与测量值、峰值与平均值、运行值与闲置值、辐射值与对流值。此外，还简要介绍了实习工程师使用实验结果估算设备冷负荷的指南。单元:双引文:研讨会，ASHRAE交易，第105卷，第。1999年2月2日，西雅图

Measurement of the heat loss from equipment in buildings is necessary in order to make accurate assessments of its impact on cooling loads. Recent advances in the design of buildings and improvement of the thermal characteristics of insulation materials and building envelope systems have significantly reduced the cooling load from external sources; however, the addition of various types of office, laboratory, and hospital equipment to buildings has become a major source of internal cooling load. Unfortunately, accurate information on the total heat gain from equipment is lacking in current handbooks. Some equipment includes a nameplate rating showing total power consumption, while other equipment does not have this. Some manufacturers measure maximum electric power consumption by the equipment and list that as power ratings on the nameplate or in the equipment literature, while some others list the maximum power capacity of the system. Since the manufacturers' power ratings, if reported, are usually based on instantaneous measurement while equipment is working at maximum capacity, use of equipment nameplate values for cooling load calculations may lead to oversizing of air-conditioning equipment, resulting in extra initial cost as well as higher operating costs. On the other hand, underestimating the cooling load may result in insufficient cooling capacity.Another factor affecting calculation of cooling load is the split between the radiant and convective heat load from the equipment. The convection portion of the heat transferred from the equipment to the surroundings is an instantaneous load, since it is added to room air by natural or forced convection without time delay, whereas the radiation portion is absorbed by the surfaces of the room and then dissipated over time. Accurate determination of cooling load is important in proper sizing of airconditioning equipment. This article presents experimental results for the total heat gain and radiant/convective split from equipment in offices, hospitals, and laboratories. The nameplate vs. measured values, peak vs. average values, operational vs. idle values, and radiant vs. convective values are compared and discussed. Furthermore, a brief guideline for use of the experimental results by practicing engineers for estimating equipment cooling load is presented.Units: Dual