PQM-T20-C-A输入模块,GE使用产品PQM-T20-C-A
降额曲线：ALG392为了获得最大性能和模块寿命，模块应在最大负载电阻下运行卸载热量。模块热降额取决于电压水平以及电流和电压的使用输出。以下前两个图表显示了仅限电流模块的最高周围空气温度在30 VDC和26.5 VDC下。混合电流和电压输出在下面所示的示例中，电压通道具有2千欧负载，电流通道具有短路负载。
PQM-T20-C-A输入模块要确定混合电流和电压输出的最大工作温度，请选择对应于所用电压通道数量的下表。例如，一个模块使用2电压通道和3个电流通道。总通道数为5，最高工作温度约52.5°C：电流和电压范围和分辨率在4到20mA范围内，模块扫描PLC的输出数据，使4mA对应于0的计数，20mA对应32000计数。在0到20mA的范围内，用户数据被缩放为0 mA对应于0的计数，20mA对应于32000。在0到20mA模式下，最大值为32767提供约20.5mA的最大输出。在当前模式下，模块还报告开环PLC故障。对于默认单极模式（0至+10伏）下的电压操作，对数据进行缩放，使0伏对应0和+10伏的计数对应32000的计数。在此模式下，高达32767的值将创建一个过量程输出约为10.24伏。在-10至+10伏范围内，数据按比例缩放，使-10伏对应于-32000和+10伏的计数对应于+32000的计数。在此范围内，从-32767到+32767的输出值会导致超范围大约-10.24伏到+10.24伏。电流和电压范围的比例如下所示。
Derating Curves: ALG392
For maximum performance and module life, the module should be operated at maximum load resistance to
offload heat. Module thermal deratings depend on the voltage level and the use of current and voltage
outputs. The first two charts below show the maximum surrounding air temperature for current-only modules
at 30 VDC and at 26.5 VDC.Mixed Current and Voltage Outputs
In the example shown below, voltage channels have 2 KOhm loads and current channels have shorted loads.
To determine the maximum operating temperature for mixed current and voltage outputs, select the line in the
chart below that corresponds to the number of voltage channels being used. For example, a module uses 2
voltage channels and 3 current channels. The total channels are 5, and the maximum operating temperature
is approximately 52.5°C:Current and Voltage Ranges and Resolution
In the 4 to 20mA range, the module scans output data from the PLC so that 4mA corresponds to a count of 0,
and 20mA corresponds to a count of 32000. In the 0 to 20mA range, user data is scaled so that 0 mA
corresponds to a count of 0 and 20mA corresponds to 32000. In 0 to 20mA mode, a value up to 32767
provides a maximum output of approximately 20.5mA. In current mode, the module also reports an open loop
fault to the PLC.
For voltage operation in the default unipolar mode (0 to +10 volts), data is scaled so that 0 volts corresponds
to a count of 0 and +10 volts corresponds to a count of 32000. In this mode, a value up to 32767 creates an
overrange output of approximately 10.24 volts.
In the -10 to +10 volt range, data is scaled so that -10 volts corresponds to a count of -32000 and +10 volts
corresponds to a count of +32000. In this range, output values from -32767 to +32767 result in an overrange
of approximately -10.24 volts to +10.24 volts.
Scaling for both current and voltage ranges is shown below.
