(under construction)
Surge ratings
Per IEC 61326-1:2021 "Electrical equipment for measurement, control and laboratory use – EMC requirements",
required surge rating for DC ports can vary between N/A to ±1kV line-to-line (2Ω) & ±2kV line-to-ground
(12Ω). If DC voltage is limited to ≤60V coming from a 'clean' power source over less than 30m of indoor wiring, then
no testing is required, even for the so-called 'industrial electromagnetic environment'.
In our opinion, these devices can easily sit at the end of fairly long cables which share conduits with other mains cabling,
or which are installed outdoors. Such gives plenty of opportunity for lightning surges to couple into our low-voltage signals...
The higher rating have the additional benefit that surge endurance is almost infinite at the 'mandatory' surge voltages. That's
because protective components such as gas discharge tubes and metal oxide varistors have a finite energy handling capability.
Every absorbed surge does a bit of permanent damage; big surge, big damage, small surge, small damage. And in order to pass
an EMC test, the protective components have to survive only 10 surges at the highest applicable level. The varistor in our
6kV-rated devices can handle about 15 strikes at 6kV/3kA and this increases to almost 10k strikes at the more reasonable
1kV/500A surge. A device designed for the latter can pass EMC by handling only 15 strikes.
These ratings are partly similar to the American standard IEEE/ANSI C.62.41.2, category C-low. This standard is about commercial lighting, industrial lighting and lighting in parking garages. So about outdoor electronics in the vicinity of buildings.
| Pulse, voltage & impedance: | Specifiation: | Requirement: |
|---|---|---|
| DC input to ground | 1.2/50µs ±6kV 2Ω | PASS, B |
| DC input to earth | 1.2/50µs ±6kV 12Ω | PASS, B |
| Ground to earth | 1.2/50µs ±6kV 12Ω | PASS, B |
| Shield to earth | 1.2/50µs ±6kV 12Ω | PASS, B |
| Grounds across isolation | 1.2/50µs ±6kV 12Ω | PASS, B |
| Communications port transverse H/L | 1.2/50µs ±6kV 2Ω | PASS, B |
| Communications port transverse H/L/ground/earth | 1.2/50µs ±6kV 12Ω | PASS, B |
| Communications port CM to ground | 10/700µs ±6kV 15+25Ω | PASS, B |
Other standard tests
| Description: | Standard: | Specifiation: | Requirement: |
|---|---|---|---|
| ESD | IEC 61000-4-2:2009 | ±8kV contact, ±15kV air | PASS, B |
| Radiated immunity | IEC 61000-4-3:2020 | 10V/m | PASS, A |
| EFT/Burst | IEC 61000-4-4:2012 | ±4kV 5kHz and 100kHz | PASS, B |
| Conducted immunity | IEC 61000-4-6:2014 | 140dBµV | PASS, A |
| Conducted immunity LF | IEC 61000-4-16:2016 | Level 3; between 1 and 10Vrms up to 150kHz | PASS, A |
| Ripple on DC inputs | IEC 61000-17:2002 | 15% on VIN,MIN and VIN,MAX | PASS, A |
| Dips & interruptions | IEC 61000-29:2002 | Performance A at least up to 1s, performance B for >1s | PASS, A/B |
Custom tests
These tests primarily concern with wiring errors during installation.
| Description: | Specifiation: | Requirement: |
|---|---|---|
| DC reverse polarity | −VIN,MAX: 15min | PASS, B |
| DC overvoltage | VIN,MAX + 25%: 15min | PASS, A |
| DC overvoltage | VIN,MAX + 50%: 15min | PASS, C 1) |
| AC power | VRMS ≤ VIN,MAX: 15min | PASS, B |
| AC mains voltage | 250VRMS 50Hz: 15min | PASS, C 1) |
| DC voltage to communications ports, CM and DM | 125% × VIN,MAX: 15min | PASS, B |
| AC mains voltage to communications ports, CM and DM | 250VRMS 50Hz: 15min | PASS, C 1) |
1) Serious overvoltages will trip a thermal cut-out or blow the (socketed) fuse inside the device.
