Can the MQTT user password be something other than the Device Token?

Can the MQTT user password be something other than the Device Token?

I have a Milesight device that I would like to connect to Tago to send data via MQTT. 
However, the device has a limit on the number of characters that can be input into the password field and the Device token does not fit. 
Is there an alternative way of setting user name and password required for the connection?