Laserfiche WebLink
representing sum check (2 digits), sensed concentration (8 digits), and calibration factor <br /> (%,4 digits). The concentration in gg/m3 is obtained by multiplying the sensed <br /> concentration times the calibration factor and dividing by 100. <br /> 10.0 ANALOG SIGNAL OUTPUT <br /> 10.1 Analog Output Description <br /> The personalDataRAM incorporates the capability to provide both a voltage and a <br /> current signal output directly proportional to the sensed concentration of airborne <br /> particulates. Both these analog signal outputs are concurrently available.These outputs <br /> are provided,principally,for fixed point applications with hard-wired installations, <br /> such as for continuous HVAC monitoring and control. <br /> The particulate concentration range corresponding to the output voltage and current <br /> ranges (0 to 5 V and 4 to 20 mA) can be user selected (via a PC). The most sensitive <br /> range available is 0 to 0.100 mg/m3, and the least sensitive range is 0 to 400 mg/m3. For <br /> example,if the user selects the analog output range of 0 to 0.400 mg/m3 then the analog <br /> output signal levels, at a concentration of 0.200 mg/m3,would be 2.5 V and 12 mA. <br /> Selection of the concentration range of the analog output must be performed on the PC. <br /> This range is independent of the digital display, data logging and real-time digital <br /> output range which are controlled automatically (auto-ranging). <br /> Enabling the analog output increases the current consumption from the power source <br /> (battery or power supply) of the personalDataRAM by typically 5 mA when no load is <br /> connected to the analog signal current output. If such a load is connected then the <br /> current consumption of the personalDataRAM further increases by the magnitude of the <br /> output signal current(up to a maximum increment of 20 mA). Therefore, when not <br /> using the analog output,it is advisable to disable that output(see Section 8.2) in order <br /> to minimize power consumption (this is important only when powering the <br /> personalDataRAM from a battery source). <br /> 10.2 Analog Output Connection <br /> The personalDataRAM is provided with a cable (model pDR-ANC) which has a 6- <br /> contact plug at one end and flying leads at the other.There are 4 leads for the analog <br /> and alarm outputs.The additional two contacts of the connector are used only for <br /> digital communication with a PC, for which a separate cable (model pDR-DCC) is <br /> provided. <br /> Counting from top to bottom on the personalDataRAM connector receptacle,contact#1 <br /> is the positive 4- 20 mA analog output,contact#2 is the alarm output,contact#5 is the <br /> common ground (return for all signals), and contact#6 is the positive 0- 5 V analog <br /> output. <br /> 26 <br />