IC693CMM301通用電氣
將操作控制器周圍的空氣保持在50°C（122°F）以下。定期檢查空氣溫度，以：確保未超過此規格。
注意安全超過規定的工作溫度限制可能會產生不利影響并可能導致控制器損壞。
當控制器安裝在部分或完全封閉的面板中時，建議使用強制空氣通風，或機柜（如NEMA 1）；如右圖所示。當存在清潔空氣時，排氣扇通常安裝在頂部以及形成在面板底部的百葉窗。然后，空氣在站殼之間向上吸入。當空氣含有顆粒物，風扇和過濾器通常位于面板底部，百葉窗位于頂部。過濾現在，空氣被迫在站殼之間向上流動。過濾器必須定期維修。只能使用高質量、安靜運行的風扇。
此外，風扇不應產生電噪聲這可能干擾電子儀器。
密封柜（如NEMA 12或4X），包含：不產生顯著熱量的設備
應包含用于強制空氣流動的再循環風扇
設備周圍和整個機柜防止熱點發展。
強制通風在非常高的密度下可能需要調節面板或控制臺。定期更換或清潔空氣過濾器。
污染物控制器外殼開槽，以允許清潔冷卻空氣。液體和腐蝕性氣體必須：不允許進入案件。是否控制器位于控制室或現場安裝。它必須：防止雨水、空調冷凝物，
以及與設備和工藝相關的流體和氣體。長時間接觸污染物可能導致：故障。
工業環境通常含有空氣污染物顆粒污染物。顆粒物，通?；覊m和污垢，具有研磨性，可導致間歇性連接。電路板上的一層灰塵會干擾部件散熱，并可能吸收其他空氣污染物。擴展
暴露于這些污染物可能導致：故障。
盡管353塊板具有保護涂層，但以下步驟可以減少與污染相關的
設備故障：風機數量：每16個站一臺或面板寬度3英尺。
進氣口：每個風扇30 in2。如果使用過濾器，則必須定期更換（將入口增加至50 in2）。
Keep the air surrounding an operating controller below 50°C (122°F). Check air temperature periodically to
ensure that this specification is not being exceeded.
CAUTION
Exceeding the specified operating temperature limits can adversely affect
performance and may cause damage to the controller.
Forced air ventilation is recommended when controllers are mounted in a partially or completely enclosed panel or
cabinet (e.g. NEMA 1); as shown at right. When clean air is present, exhaust fans are often mounted across the top
of a panel and louvers formed in the panel bottom. Air is then drawn upward between the station cases. When air
contains particulate matter, fans and filters are generally located at the panel bottom and louvers at the top. Filtered
air is now forced upward between the station cases. Filters must be serviced periodically.
Only high quality, quiet running fans should be used.
Also, the fans should not generate electrical noise
which could interfere with electronic instruments.
A sealed cabinet (e.g. NEMA 12 or 4X) containing
equipment that does not generate significant heat
should contain a recirculating fan for forcing air flow
around equipment and throughout the cabinet
preventing hot spots from developing. Forced air
conditioning may be required in very high density
panels or consoles. Periodically change or clean air
filters.
CONTAMINANTS
The controller case is slotted to permit circulation of
clean cooling air. Liquids and corrosive gases must
not be allowed to enter the case. Whether the
controller is in a control room or field mounted it must
be protected from rain, air conditioning condensate,
and plant and process related fluids and gases.
Extended exposure to contaminants can result in
malfunctions.
Industrial environments often contain airborne
particulate contaminants. Particulate matter, usually
dust and dirt, is abrasive and can cause intermittent
connections. A layer of dust on circuit boards can
interfere with component heat dissipation and can
absorb other airborne contaminants. Extended
exposure to these contaminants may result in
malfunctions.
Although 353 boards have a protective coating, the
following steps can reduce contaminant related
equipment malfunctions: No. of Fans: One for each 16 stations or 3 ft. of panel width.
Air Inlet: 30 in2 for each fan. If filters are used, they must
be changed periodically (increase inlet to 50 in2).
