Learn the signal
before the part.
Original explanations and diagrams for the low-voltage signals that make industrial equipment readable.
4–20 mA vs 0–10 V: the practical difference
Two common analog signals, explained by wiring, distance, fault behavior, and the input card waiting at the other end.
PNP vs NPN sensors without the guessing
See what sourcing and sinking mean at the terminal, then match the sensor to the PLC input that can actually read it.
M12 connector pinouts: A-coded, D-coded, and the traps
A visual index for the connector families that look similar until the network refuses to come online.
RTD vs thermocouple: what changes at the input
A field-minded comparison of sensing principle, wiring, compensation, and the errors that masquerade as bad hardware.
What sensor shielding actually does
Noise has a route. Learn how cable routing, drain wires, and reference points change what the analog input sees.
Loop power, explained without the hand-waving
The supply, the transmitter, and the load all share one loop. Here is what each one is allowed to consume.
IO-Link vs. discrete sensors: what diagnostics change
When parameterization and device diagnostics are worth more than a simple on/off state.
RS-485 termination: why Modbus fails in the plant
Topology, termination, biasing, and the meter-first checks that expose a fragile bus.
24 V DC voltage drop: a field calculation for ghost faults
Calculate the full loop and measure at the device before blaming the power supply.
Inductive proximity sensors: material, range, and hysteresis
Why the target and mounting details matter more than a nominal sensing distance.
PLC raw counts to engineering units: a scaling check
Use live zero, endpoints, and known test inputs to catch bad values before changing hardware.