3BHE036204P201工控卡件，3BHE039204P106用戶手冊
輸出可能是“浮動的”，但是與“地”的隔離并不充分。一些“醫(yī)療級”AC/DC具有操作者保護措施（MOOP），但由于輸入/輸出和輸出/接地的隔離不足，而且AC/DC隔離耦合電容也不夠低，所以不適合直接與患者連接。雖然也有具備雙重患者保護（2MOPP）的AC/DC可以使用，但功率范圍有限而且價格昂貴。多通道傳感器通常需要多個相互隔離的電源軌，但可以肯定的是，只有完全定制的2MOPP AC/DC才會具備全部所需的電源軌。DC/DC可以構成隔離系統(tǒng)的一部分
3BHE036204P201工控卡件，3BHE039204P106用戶手冊一種解決方案是使用標準的2MOOP醫(yī)療級隔離的AC/DC轉換器，然后以一個或多個醫(yī)療級DC/DC轉換器來為傳感器增加另一級的隔離。這些轉換器提供所需的傳感器電壓軌，如果它們具有高隔離和低耦合電容就可以進一步成為隔離系統(tǒng)的一部分，來滿足最嚴格的“心臟漂浮”（CF）類設備的應用。圖2顯示了具有接地外殼或 “Class I” 電氣配置系統(tǒng)的典型連接使AC/DC具有2MOOP，DC/DC轉換器也需要2MOPP，因為有未指定的設備（SIP/SOP）連接到DC/DC輸入端，這可能在故障的情況下產生危險電壓。
如果設備是“Class II”電氣設備，即沒有接地連接，并使用未指定外部連接的塑料外殼，但如果AC/DC至少具有2MOOP的隔離，那么DC/DC轉換器可以只需要1MOPP等級的隔離（D），用于直接與患者連接的應用。DC/DC通常只需提供低功率電源，不僅體積小成本也低。
DC/DC轉換器的典型應用如圖3所示。這里使用一個儀表放大器作為ECG傳感器，為分析提供數字數據。另一個DC/DC為驅動器供電，驅動器為患者進行某種刺激，并且與傳感器隔離。數據則用光偶進行隔離。儀表放大器通常需要+/-5V的電壓，驅動器則需要+12V的電壓。由穩(wěn)壓系統(tǒng)電壓供電的兩個2W板載DC/DC轉換器提供隔離的電壓軌。由于是穩(wěn)壓輸入且負載恒定，因此DC/DC可以是簡單、低成本的 “非穩(wěn)壓” 轉換器，只需百分之幾的負載調節(jié)率，即可獲得足夠的性能。DC/DC轉換器可以為其他測量或刺激通道提供更多隔離的電源軌。DC/DC轉換器的小尺寸和設計使其具有極低的耦合電容，因此漏電流極小。
DC/DC轉換器會產生噪聲
所有高效率的DC/DC轉換器都是“開關式”電源，因此會產生傳導和輻射電磁噪聲。
power supply and maintain the operation of key systems. Weidmuller protop series power supply is resistant to high temperature and humidity, has better protection, and is not easy to "condense". At the same time, the maxguard electronic fuse for electronic load monitoring is installed on the output side of the power supply, which can increase the protection level and carry out rapid fault diagnosis. Weidmiller's solution in the form of "combined fist" ensures that the processing of tobacco is more smooth. The high reliability, durability and compactness of Weidmuller protop power supply make it the first choice of customers. Thanks to the patented DCL Technology (DCL - output dynamic overcurrent), protop has a very good dynamic range of output overcurrent, which can reliably trigger the circuit breaker and drive the start and operation of high-power equipment. In the threshing and redrying production line, protop provides stable, lasting and efficient DC output. At the same time, the production line also requires continuous and stable power margin, long service life and low sensitivity to overvoltage, ambient temperature or vibration, which are what Weidmuller protop power supply is good at.
The innovative electronic load monitoring maxguard integrates the equipotential distribution terminals that used to be installed independently to form a 24V DC power distribution system, which can save up to 50% of the space and 20% of the installation time. Maxguard has a modular design, which shows its advantages in the threshing and redrying production line incisively and vividly. Its transverse connection mode between various modules
