Method of monitoring joint and contact conditions in an electrical network

A method of monitoring joint and contact conditions in an automatic transfer switch, comprising:

• collecting electrical signals at a plurality of measurement locations in the automatic transfer switch including a power switching mechanism having a contact, the measurement locations being associated with a plurality of power sources and a load over a predetermined period, the measurement locations including a first input joint for the contact of the automatic transfer switch, the first input joint connected to a primary power source, a second input joint for the contact, the second input joint connected to a secondary power source and an output joint of the contact, the output joint connected to the load, the electrical signals including voltages and load current, the contact being operable to selectively switch between the first input joint to provide the load with power from the primary power source and the second input joint to provide the load with power from the secondary power source;
• obtaining deltas between source voltages and corresponding load voltage measured at the measurement locations over the predetermined period, the deltas including a voltage drop between input voltage measured at the first input joint for the primary power source and output voltage measured at the output joint for the load or a voltage drop between input voltage measured at the second input joint for the secondary power source and the output voltage measured at the output joint;
• comparing the deltas with thresholds obtained during healthy condition, thresholds having been derived based at least in part on temperature changes measured at the measurement locations;
• determining that the deltas fall outside of the thresholds;
• and
• in response to determining that the deltas fall outside of the threshold,
• transmitting an alert to a user, the alert indicating a detection of one or more failure modes at the measurement locations.