Emerson Exchange 365

Recently, a wastewater customer in North Carolina contacted us for help configuring their 1066-C-HT-60 which is connected to the DCS/PLC and had 23VDC as measured at the analyzer terminal. This is a quick recap of the troubleshooting steps and the solution:

Challenge: Output is stuck at 4mA in a 0-1000uS/cm process

Troubleshooting:

Steps taken by customer:

• Reset the analyzer [did not work]

• Checked for fault messages [none found]

• Did a simulation on the analyzer [able to simulate, but live output reading was still stuck]
                

Steps taken by Emerson Support team:

• Check the proper units when ranging (uS/cm or mS/cm) [customer verified range was in uS/cm]

• Verified the value of conductivity VS live output:

  S1: 524.9uS/cm

  T1: 67.5F

  O1: 4.01mA

  O1%: 0.1%  

Conclusion: An output range misconfiguration.  Typically the computation is:

• • If range is set correctly to 0-1000uS, then (525uS/1000uS)*16+4 = 12.4mA
  • If range is set 0to 1000mS, then (525uS/1000000uS)*16+4 = 4.01mA

Solution: Asked customer to REVERSE the output settings to verify ranging issue.  After doing so, the output was no longer stuck at 4mA.

*This solution applies to the following Liquid Analyzer models: 1066, 1056, 1057, 5081, and 56