Plural component pumping system

A plural component pump system for delivering a plurality of liquid components at a selected ratio, the plural component pump system comprising:

• a first brushless DC motor configured to drive a first pump configured to pump a first liquid component to an output;
• a second brushless DC motor configured to drive a second pump configured to pump a second liquid component to the output;
• a first controller configured to control the first brushless DC motor;
• a second controller configured to control the second brushless DC motor;
• an input component configured to receive an input from a user, wherein the received input specifies an alarm threshold, wherein the alarm threshold is a difference in pressure between the first pump and the second pump;
• and
• an indicator component configured to provide an indication when the alarm threshold is exceeded;
• and
• a communication interface between the first controller and the second controller, wherein:
• the first controller is configured to send a first signal to the second controller using the communication interface, the first signal being indicative of a motor characteristic, corresponding to the second brushless DC motor;
• and
• the second controller has a plurality of control modes for the second brushless DC motor, including at least:
• a linked mode wherein the second controller is configured to control the second brushless DC motor based on the first signal received from the first controller, and wherein the first controller, upon detecting a change in a motor characteristic of the lust brushless DC motor, is further configured to automatically send a second signal indicative of a change in the motor characteristic corresponding to the second brushless DC motor, directly to the second controller such that the ratio between a first magnitude of the first liquid component and a second magnitude of the second liquid component is maintained, and, while in the linked mode, a pressure control function of the second pump is disabled, such that the ratio between the first magnitude of the first liquid component and the second magnitude of the second liquid component is governed by a characteristic other than a pressure of the second pump;
• and
• an unlinked mode wherein the second brushless DC motor is operated by the second controller independent of the first signal.

A method of operating first and second pump units to deliver plural components at a particular ratio, the method comprising:

• operating the first and second pump units in a first mode of operation, wherein the first mode comprises operating the first pump unit independently from the second pump unit, such that each of the first and second pump units operate independent of the particular ratio between a first magnitude of a first liquid from the first pump unit and a second magnitude of a second liquid from the second pump unit, and wherein the first pump unit is controlled by a first pump controller and the second pump unit is controlled by a second pump controller;
• receiving an input on an input component, wherein the input specifies a second mode of operation;
• switching an operating mode of the first and second pump units, based on the received input, from the first mode to the second mode, wherein the second mode comprises operation of the second pump unit based on the first pump unit such that the second pump controller is controlled by the first pump controller such that the particular ratio is maintained, and, wherein, a pressure control function of the second pump unit is disabled in response to operating the first and second pump units in the second mode;
• sending a first signal from the first pump controller to the second pump controller based on the particular ratio in response to operating the first and second pump units in the second mode;
• and
• sending a second signal from the first pump controller to the second pump controller based on a detected change in an operating characteristic of the first pump unit, the second signal being indicative of a change to an operating characteristic of the second pump unit;
• and
• wherein each of the first and second pump units comprises a brushless DC motor configured to drive a fluid pump.