mburnett Posted August 21, 2014 Share Posted August 21, 2014 I have an existing UMAC system and I'd like to set up two temperature control loops. Nothing fancy, just control the setpoint and be able to know what the temperature is. I haven't chosen sensors yet, so I have a lot of options. On/off control is probably good enough. I know Ethernet to external controllers is an option but expensive. Any ideas? Link to comment Share on other sites More sharing options...
Sina.Sattari Posted August 21, 2014 Share Posted August 21, 2014 The most inexpensive method is to use Modbus communication. This is a software option which can be used directly on the UMAC CPU. You can maintain your PC communication on the Ethernet with UMAC and also talk to a Master or Slave Modbus device through an Ethernet switch. Just a word of caution about the communication speed: if Modbus communication is used on Turbo PMAC through the CPU along with high throughput of data (for example running a large G-Code through dual ported ram) between PC and UMAC, the throughput of the data will be affected since both processes use the same Ethernet resource. If you don't have high throughput communication and only running an HMI with a couple of dozen variables going back and forth, there is hardly any effect visible on communication performance. Link to comment Share on other sites More sharing options...
JeffLowe Posted August 25, 2014 Share Posted August 25, 2014 I have an existing UMAC system and I'd like to set up two temperature control loops. Nothing fancy, just control the setpoint and be able to know what the temperature is. I haven't chosen sensors yet, so I have a lot of options. On/off control is probably good enough. I know Ethernet to external controllers is an option but expensive. Any ideas? The PIP loops of the PMAC do a good job of controlling many different kinds of loops including temperature. Signal conditioning modules from various sources can convert RDT, Thermocouple, or Thermistor to 0-10V which can be brought in through the ACC28E. For outputs, simple bang-bang could be done under plc control using an I/O bit and an SSR. Moving up a bit in sophistication, you could use the DAC outputs of a motor channel to control a proportional SSR as well. Old school N-Z tuning methods work well, Probably will want to use servo cycle extension Ix60 to slow the servo update down to 10-20x the response time of the system. Link to comment Share on other sites More sharing options...
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