PLBoudette
Member
I'm working with a GE Fanuc Series 90-30 PLC and am coordinating it through Modbus protocol to a MSA Ultima XE Gas Sensor with Modbus and I have two questions:
The first regards the 90-30 CPU. I set up a bench test with a spare CPU363 and am able to communicate with the unit. However, I will be installing this with a CPU360 in the field (the site is far away and I don't have a spare CPU360 lying around). With the CPU363, I can configure port 2 (rs-485) in the hardware configuration and using the CommReq function. However, when I look at the program they have with a CPU360 (this job is an add-on to a running program where the PLC cannot be shut down, i.e. no hardware config. download) there is no configuration for port 2. If I just use the CommReq function to set up port 2, will this work without shutting the PLC down?
And the 2nd question is, some of the registers from the gas sensor are formatted for single precision floating point. When I receive the data from the unit in the PLC and compare it to what is configured locally at the unit, they differ greatly. Do I need to convert the register to a floating point value and if so, how? I'm relatively competent with GE Fanuc programming but never had to use floating point so I'm not quite sure how to do this.
Any help is greatly appreciated. Thanks.
Pete
The first regards the 90-30 CPU. I set up a bench test with a spare CPU363 and am able to communicate with the unit. However, I will be installing this with a CPU360 in the field (the site is far away and I don't have a spare CPU360 lying around). With the CPU363, I can configure port 2 (rs-485) in the hardware configuration and using the CommReq function. However, when I look at the program they have with a CPU360 (this job is an add-on to a running program where the PLC cannot be shut down, i.e. no hardware config. download) there is no configuration for port 2. If I just use the CommReq function to set up port 2, will this work without shutting the PLC down?
And the 2nd question is, some of the registers from the gas sensor are formatted for single precision floating point. When I receive the data from the unit in the PLC and compare it to what is configured locally at the unit, they differ greatly. Do I need to convert the register to a floating point value and if so, how? I'm relatively competent with GE Fanuc programming but never had to use floating point so I'm not quite sure how to do this.
Any help is greatly appreciated. Thanks.
Pete