Hydrogen-FC Ltd.

On these case, we build system with PLC K120S from LS Industrial Systems as Master device and VSD (Variable Speed Drive) Altivar-31 from Schneider Electric as 1st Slave device and iG5A from LS Industrial Systems as 2nd Slave Device. All communication between Master and Slave device performed by Modbus RTU protocol.

PLC K120S with K7M-DR20U type is low price PLC with powerful built-in functions, like : PID function, Modbus RTU protocol, High Speed Counter (HSC), Pulse Output. Otherwise, the disadvantage of PLC K120S is could not processing floating data. All analog data will processed using integer format.

Goal target on this case is PLC K120S could set the reference frequency, acceleration, deceleration and monitor current value of output frequency, output current, output voltage and output power from each VSD. Continue Reading »

Tags: Modbus, PLC/PAC

Our previous article had explained how to configuring Modbus TCP protocol between HMI Ifix5.0 and PLC VersaMax40. So that on these article we just explain how to create register blocks and few setup on Modbus Driver v.7.42 Ifix5.0 so that HMI Ifix5.0 as Client device could send/receive data from Flow Computer OMNI6000 as Server device.

OMNI6000 is latest Flow Computer from OMNIFLOW Inc. OMNI6000 suitable to be used as deterministic electronic flow/energy correction on metering measurement of crude oils, refined products, NGLs, LPGs, ethylene, propylene, natural gas, and specially gases, such as Oxygen, Nytrogen, Hydrogen, Water, and Carbon Dioxide. OMNI6000 suitable to be used for Orifice Plate or Turbin Meter metering system. Continue Reading »

Tags: HMI/SCADA, Modbus

PID (Proportional-Integral-Derivative) controller is control loop feedback mechanism that widely used in control system. PID calculating the error value that generated by difference between feedback Process Value (PV) and Set Point (SP) PID. When error value generating, PID controller adjusting output Measurement Value (MV) to minimize error near to zero value.

Let us give some example PID Controller on Booster Pump application like on the left picture. Feedback Process Value (PV) is Actual Pressure (Bar), Set Point (SP) PID is Set Pressure (Bar), and output Measurement Value (MV) is VSD Reference Frequency (Hz).  This is the mechanism. Whenever the difference between PV & SP negative, PID Controller increasing output MV. Otherwise when the difference between PV & SP positive, PID Controller decreasing output MV. How fast the PID Controller could execute error calculation are depend on cycle speed on each controller and type of PID function.  There are several PID function base on control actions, which are P, I, PI, PD. PI function is widely used for Booster Pump application. Continue Reading »

Tags: HMI/SCADA, PLC/PAC

VersaMax40 is one kind of VersaMax Micro Plus Controllers from GE Intelligent Platforms that have more enhanced features like : more memory (for boolean, integer, floating data), real time clock (RTC),  optional port for industrial protocol communication, high speed counter (HSC) up to 4 at 100kHz, pulse width modulation (PWM) up to 4 at 65kHz, motion commands, PID function and subroutines. VersaMax40 limited to 152  maximum physical I/O with up to 4 I/O expansion units.

VersaMax40 have 1 RS-232 and second port option for RS-232/RS-485/USB/Ethernet. Usually, 1 RS-232 port defined as  SNP port mode for PLC programming with Proficy Machine Edition. On This application we will use second port option to add ethernet communication module – IC200UEM001. With this communication module we could self-defined VersaMax40 as Server device that communicate with HMI Ifix5.0 as Client device via Modbus TCP protocol. With ethernet communication module, VersaMax40 could handle up to 8 Clients device simultaneous on Modbus TCP network. Please following GFK-2436B for detail instruction. Continue Reading »

Tags: HMI/SCADA, Modbus, PLC/PAC