Basic Fax Machine Settings for VoIP

This page is part of the Network and QoS guides.

Fax Settings

What are the Basic settings needed for a fax machine to be used in a Voice Over IP phone system?

Basic Settings for VoIP

The following are the recommend settings for most fax machines

• Signal rate to be at 9600bps and not higher than 14,400, On brother fax machines set to Normal, Basic, or VoIP.
• ECM: Disabled
• If available, turn on VoIP Mode on applicable fax machines, this automatically reduces baud rete and disables ECM.
• If VoIP mode in not available, enable Over seas mode (if available). On applicable fax machines, this automatically reduces baud rate and disables ECM.
• If equipped with “Distinctive Ring,” turn off

Speeds

If the fax goes through at a speed greater than 14400 bit/s or the fax doesn’t succeed, you likely have G3 enabled on your fax machine. It’s recommended that you disable it as this may lead to failures with other Super G3-capable fax machines. Call your fax machine using a cell or office phone. Right at the beginning of the call, you should hear a clear, continuous fax tone; if the fax tone sounds like it is interrupted at regular intervals, your fax machine needs further adjustment. Speeds faster than 14400bps will magnify any latency, jitter or packet loss.

• The fax machine’s speed is set to 33,600bps instead of the recommended speed
• “Super G3” is enabled
• “V.34” in enabled
• “V.8” is enabled

Error Correction

Why Disable ECM, V.34 and V.8?

ECM (Error Correction Management) analyzes incoming data for corruption, which can increase latency. In some cases, this may compromise image quality. Our recommendation is to disable V.34 and ECM because faxes can get cut off during transmission or partial faxes are being received. Although there are benefits to using V.34 and ECM — V.34 optimizes fax speed and reliability, and ECM automatically detects and corrects errors encountered in the fax transition process — there are some fax machines and systems that encounter problems with V.34 and ECM modes.

Other Fax Machine Settings

The methods to configure these settings vary from machine to machine, and there are too many variations for us to list here. Some enterprise fax machines require a licensed service technician to modify these settings, as they're only found in a hidden admin menu. Here are a few general pointers to help you or your technician ensure the correct settings on your fax machine.

Brother Fax Machines

VoIP Compatibility Settings

Speed Settings

Most Models - Single Speed Selection

Faxing with Brother Fax machines over VoIP should be accomplished using the following settings. 

• Set the Baud rate to 9600 for a slower speed by choosing Basic as the Configuration Setting. 
• Turn off or disable ECM (Error Correction Mode) by enabling Overseas Mode. 
• These settings can be difficult to make on some older Brother fax machines but have become easy on many new models.

Other Models - TX/RX Speed Selection

You must configure the settings for TX and RX separately for some Brother Fax machines. In those cases, if you can figure out the RX settings according to the above, you can match the TX settings to the RX settings.

We list here the configuration settings location for Brother fax machines as these are the ones, we experience the most common problems with. You can search the internet or consult your user manual for these common settings related to your fax machine.

Often the TX and RX behavior are set through a single setting on the fax machine.  On Brother fax machines, for example, to set the fax speed correctly you would need to select 'Normal' compatibility:

• Open MENU
• Select Fax
• Select Miscellaneous
• Select Compatibility
• Choose 'Normal' or ‘Basic’

FAX1360, FAX1860C, FAX1960C, MFC240C

• Press the Menu key.
• Press 2, Press 0, then Press 2 again.
• Hit the Up or Down Arrow and select Basic.
• Press the OK Key.
• Press the Stop or Exit Key.

FAX1840C, FAX1840CN, FAX1940CN, FAX2810 FAX2910, FAX2920

• Press the Menu/Set key.
• Press 2, Press 0, then Press 1.
• Hit the Up or Down Arrow key and select Basic.
• Press the Menu/Set key.
• Press the Stop or Exit Key.

Overseas Mode

FAX1360, FAX1860C, FAX1960C, MFC240C

• Under Fax Settings which can differ depending on exact machine navigate to Additional Functions, which will display the menus.  The Additional Function Key Will Blink.  Use the Left (-) and Right (+) arrow to select the menu you want, in this case Fax Settings.  Press Set.
• Press the Fax key to illuminate it.
• Load your document.
• Press the Menu key.
• Press 2, Press 2 again, then Press 7.
• Hit the Up or Down Arrow and select On.
• Press the OK Key.

FAX1840C, FAX1840CN, FAX1940CN, FAX2810 FAX2910, FAX2920

• Under Fax Settings which can differ depending on exact machine navigate to Additional Functions, which will display the menus.  The Additional Function Key will Blink.  Use the Left (-) and Right (+) arrow to select the menu you want, in this case Fax Settings.  Press Set.
• Press the Fax key to illuminate it.
• Load your document.
• Press the Menu/Set key.
• Press 2, Press 2 again, then Press 7.
• Hit the Up or Down Arrow and select On.
• Press the Menu/Set key.

If you have any questions about this process, or if you need assistance, please reach out to our Support Team by dialing HELP(4357) on your desk phone, calling (972) 924-6488, or submitting a ticket.