Adaptive logic board for variable speed drive
The present disclosure relates to an adaptive logic board that includes a signal sensing circuit configured to receive an input signal as an electrical current. The signal sensing circuit includes a plurality of resistors and a plurality of switches configured to electrically couple or electrically decouple the plurality of resistors from the signal sensing circuit, in which each switch of the plurality of switches corresponds to a corresponding resistor of the plurality of resistors. The adaptive logic board also includes a sensing unit that is configured to measure a voltage drop of the input signal across an active resistor of the plurality of resistors.
1 . A method of operating a variable speed drive (VSD) using an adaptive logic board, comprising:
determining a size of the VSD based at least in part on a power output range of the VSD;
electrically coupling a resistor of a plurality of resistors to a signal sensing circuit of the adaptive logic board, wherein the resistor is an active resistor, and the active resistor is determined by:
evaluating the power output range of the VSD; and
selecting the resistor from the plurality of resistors based on the power output range of the VSD;
generating an electrical signal using one or more current transducers coupled to power lines of the VSD, wherein a magnitude of the electrical signal is proportional to a magnitude of an electrical current flowing through the power lines; and
instructing the VSD to adjust the magnitude of the electrical current flowing through the power lines based at least in part on the electrical signal of the one or more current transducers.
2 . The method of claim 1 , wherein determining the size of the VSD comprises transmitting an identification code from the VSD to the adaptive logic board, wherein the identification code is associated with the power output range of the VSD.
3 . The method of claim 1 , further comprising monitoring a voltage drop across the active resistor using a sensing unit disposed within the adaptive logic board, wherein the voltage drop is generated by the electrical signal, and wherein a magnitude of the voltage drop is proportional to the magnitude of the electrical signal.
4 . The method of claim 3 , further comprising interrupting the electrical current flowing through the power lines using the VSD when the magnitude of the voltage drop deviates from a target value by a predetermined amount.
5 . The method of claim 1 , further comprising determining a structure of a harness by determining a quantity of connection wires within the harness, wherein the structure of the harness is indicative of the size of the VSD.
6 . The method of claim 1 , further comprising determining the size of the VSD based on an operator input provided via an input device of the adaptive logic board.
7 . A heating, ventilation, air conditioning, and refrigeration (HVAC&R) system, comprising:
a motor configured to drive a compressor;
a variable speed drive (VSD) coupled to the motor, wherein the VSD is configured supply a first electric current to the motor through a plurality of power lines;
a plurality of current transducers, wherein each current transducer of the plurality of current transducers is disposed about a corresponding power line of the plurality of power lines; and
an adaptive logic board communicatively coupled to the VSD, wherein the adaptive logic board comprises a plurality of signal sensing circuits, wherein each signal sensing circuit of the plurality of signal sensing circuits is electrically coupled to a corresponding current transducer of the plurality of current transducers, wherein the plurality of current transducers is configured to generate a plurality of second electric currents, and wherein each signal sensing circuit of the plurality of signal sensing circuits comprises:
a resistor configured to receive a respective second electric current of the plurality of second electric currents; and
an adaptive sensing unit electrically coupled to the resistor, wherein the adaptive sensing unit is configured to measure a voltage drop of the respective second electric current across the resistor, the adaptive sensing unit comprises a programmable resistor electrically coupled to the resistor, and the adaptive sensing unit is configured to adjust a resistance value of the programmable resistor based on a size of the VSD.
8 . The HVAC&R system of claim 7 , wherein for each signal sensing circuit of the plurality of signal sensing circuits, the adaptive sensing unit is configured to electrically couple an active resistor of a plurality of sensing resistors to the signal sensing circuit based on the size of the VSD.