WEG CFW100 vs CFW300 VFD Option Modules from AutomationDirect

Knowing the capabilities of the CFW100 and CFW300 variable frequency drives I/O and communications options will help you decide which drive is right for you. Options that only apply to the CFW100 will be in blue. Options that apply to only the CFW300 will be in yellow. And any options that apply to both drives will be green. Both base drives with no option modules have 4 digital inputs that can be configured as NPN or PNP. The CFW300 also has an analog input, a relay output and a 10-volt supply for powering a sensor or two. Keep in mind that while it is one analog input channel, it actually uses 2 pins on the header – 1 for voltage input and 1 for current input. You can only use one or the other – you can’t use both at the same time. Having that analog input is nice because you can add a potentiometer to control the speed of the drive. The CFW100 addresses that by providing a potentiometer input module. Plug it in, modify a couple parameters and you now have speed control directly on the drive. I really like that feature. The CW300 doesn’t have a potentiometer module. I’m only showing the part number suffix. So, this part number would be CFW100-IOP. The CFW100 also has a generic input module so you can use your own potentiometer or measure whatever analog signal you want. Same rules apply, while there is only one analog input channel, you have to choose either the voltage pin of the current pin – you can’t use both at the same time. That module also adds the extra analog output. Both drives have a general-purpose analog digital relay module that provides an additional 3 digital output relays, one thermistor, which comes with the unit and an infrared input so you can control the drive with an infrared remote control, which also comes with the module. Notice that the infrared remote allows you to reverse the direction of the motor with a button press. The keypad on the drive and the remote keypad don’t have a forward reverse button. The CFW100 version of that module also has another analog input and a 10-volt reference you can use to power a sensor or two. Both drives have an analog relay module that adds an analog input, relay outputs and a 10-volt reference. The CFW100 version of the module has 1 relay output while the CFW300 has 3 outputs. The CFW300 also has an additional analog output. Both drives have a digital module which adds 4 digital inputs and the CFW300 version has an additional 3 relay outputs. And don’t forget that when using the PNP digital inputs you will need to provide an external 24 volts. The NPN inputs don’t require an external voltage. Only the CFW300 has an encoder module which has an analog input, 2 analog outputs, the encoder input, a 5-volt reference you would typically use with the encoder, and a 10-volt reference. Both drives have a remote keypad option, so you can mount the keypad and HMI away from the drive. Again, this keypad is just like the drives keypad, which means it doesn’t have a forward and reverse button. This option comes with both the keypad and the RS485 module that you need to talk to the keypad. Both drives have a standalone RS485 module, only the CFW300 has an RS232 module, and they both have a USB module which is handy for configuring or monitoring the drive with the free WPS software. But remember, on the CFW100 you have to remove that USB module if you want to plug in any other option modules because there is only one option module slot on the CFW100. While we are talking about options, I should mention that both drives have an optional RFI filter which filters the input power to the drive, so it doesn’t interfere with other equipment on the same branch circuit. The CFW100 also has an optional mounting tab kit so you can mount the drive directly to the wall instead of a DIN Rail. The CFW300 has those built in. Notice that there are only two adapters in the package, so you will need 2 packages if you want to nail down all 4 corners of the drive. The bottom line is: the drives are the same price for a given horse power, so it’s up to you. Do you prefer the smaller CFW100 drive or the more I/O options of the CFW300? For me, the base CFW300 is enough to cover my needs for most applications. I use the 4 digital inputs for a run button and a stop button, a forward and reverse switch and a local remote select switch. I use the analog input for a potentiometer, so I can control the drive's speed. And of course, there are videos showing you how to do all of that. If I really need the smaller drive size, then the base CFW100 plus one analog or potentiometer input module will give me enough to cover all of those needs. Click here to see all the WEG Variable Frequency Drive videos. Click here to learn about AutomationDirect’s free support options and click here to subscribe to our YouTube channel so you will be notified when we publish new videos.