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When using the PID loops with my D2-250, my process variable doesn look correct coming from my analog or temperature card. Whats wrong?

April 26, 2017analog coming d2-250 look loops PID process temperature

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When using the PID loops with my D2-250, my process variable doesn look correct coming from my analog or temperature card. Whats wrong?

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The Setpoint Value (SP), Process Variable (PV), Bias (Integrator) and Control Output Value (CO) are in binary format. If you use the pointer method to bring the analog signals into the CPU be aware of the format you have specified. With the pointer method, if you do not precede the number of channels constant with an ‘8’ the value is in BCD. You must do a BIN conversion before OUTing this value to Word+3 (PV). Also, make sure the proper format from the Word+5 (CO) is in the proper format when it reaches its module. It is in binary format when it leaves the PID loop. The loop table specifications are contained in the PID chapter of the User Manual.