Low-Cost PLC/HMI with direct inputs for temperature sensors.
New temperature controller family from Unitronics offers a low-cost PLC with an embedded HMI and direct temperature measurement inputs.
Traditionally, setting up a temperature control loop involved either a PID controller or a high-level PLC that includes PID functionality. The PID controller is usually cheaper but has to be set up as an extra unit with all that entails. The PLC is easier, but more expensive. To solve that problem, Unitronics recently launched two new Jazz PLCs that it says can fully replace the PID controller, without exceeding your budget.
The JZ10-11-UA24 offers two thermocouple/PT100 inputs, two analog inputs, and two analog outputs.JZ-11-UN20 offers one Thermocouple/PT100 input and one analog input.Both models include additional onboard digital I/Os, with up to 24 points.
Both Jazz models include 4 auto-tune PID loops. PID can be set using the onboard temperature/analog inputs and the analog or PWM (pulsed wave modulation) outputs. All onboard transistor outputs can function as PWM outputs.
Jazz also features a full-function HMI with a two line LCD text display that shows up to 60 user-designed screens, and a 16-key keypad. The multilingual display supports over 15 languages, and 20 graphic symbols.
Unitronics says its control and communication options make the Jazz units a big step up from any smart-relay—24K (virtual) of ladder logic enable flexibility and functionality. Software functions include interrupt, loops, math, and store and compare. Communication options include SMS messaging, Modbus networking and PC access via Modbus or OPC.
—Edited by Peter Welander, process industries editor, [email protected] , Process & Advanced Control Monthly eNewsletter Register here and scroll down to select your choice of free eNewsletters .
