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Keywords of this article: Rosemount. http://www.qyyb.net/rosemount The Rosemount 3144 transmitter can be used in many different applications. When selecting a suitable instrument, taking the 3144 transmitter as an example, here are some tips for determining the quality of the Rosemount 3144 transmitter: 1. When the voltage between the two wires exceeds 24V due to induced lightning or surge voltages, it must be clamped down so as not to damage the transmitter； Generally, 1–2 TVS transient protection diodes with a rating of 1.5KE are connected in parallel between the two lines; these diodes can suppress pulses with a width of 20 milliseconds that occur every 20 seconds, and they can handle a transient impact power of 1.5KW–3KW ； 2. When the primary side is overloaded, the output current must not exceed 25.000mA ±10%. Otherwise, the 24V power supply for the Rosemount transmitter and the A/D input clamping circuit within the PLC/DCS will be damaged due to excessive power dissipation. Additionally, the emitter-follower output within the transmitter will also be damaged for the same reason. In cases where there is no A/D input clamping circuit, the damage is even more severe ； 3. When the full scale is 20.000mA and the load is 250Ω, the reading at full scale of 20.000mA remains unchanged despite variations in the operating voltage from 15.000V to 30.000V ； The variation is no more than 20.000mA, within 0.5% ； 4. When the operating voltage is 24.000V and the full-scale current is 20.000mA, the reading at this full-scale current does not change as the load varies from 0 to 700Ω ； The variation is no more than 20.000mA, within 0.5%. Above, we have introduced to you four methods for determining the quality of Rosemount 3144 transmitters. In the future, when assessing instruments, you can refer to these methods. Shanghai Quanyun Instrument Co., Ltd. Contact phone: 021-57629782 Company fax: 021-57629781 Mobile number: 15801876667 Contact person: Bao QQ: 1609345838 Address: Room 519, No. 32 Xinxin Road, Chedun Town, Songjiang District, Shanghai