HM Digital PSC-154 Panel Mount EC/TDS Display New In Box January 22, 2024 by admin An alarm will sound if the TDS /EC level rises above the user-set level. TDS Range: 0 – 5000 ppm. EC Range: 0-9999 µS. 4-20mA output signal can connect to a PLC to record values. Output Signal: Digital 4-20mA. Share