Insulation Monitoring Device for DC Fast Charging Station

It seems like it's still pretty much the wild west out there as far as different standards go, what we need is one universal standard to simplify the process of slow charge vs different levels of fast charging protocols and design...so I would say you have to design to the standard being used in the geographic location you are selling in...I can tell you nothing will work that has a danger of electrocution attached....

https://greentransportation.info/ev-charging/range-confidence/chap8-tech/ev-dc-fast-charging-standards-chademo-ccs-sae-combo-tesla-supercharger-etc.html

https://en.wikipedia.org/wiki/IEC_62196

https://en.wikipedia.org/wiki/Charging_station

http://www.sendyne.com/Company/Publications/Insulation%20Monitoring%20of%20Quick%20DC%20Charging%20Stations%20v0.1.pdf

"The number of electric vehicles is constantly increasing and will grow even faster in the future. This will also help to expand the charging station infrastructure, as DC charging stations are the first choice when electric vehicles need to be charged in the shortest possible time. Electrical safety must be ensured during the charging process. For this purpose, an unearthed DC power supply system (IT system) with insulation monitoring by an insulation monitoring device (IMD) is installed. The user must never be exposed to high voltages (up to 1000 V) at any time."

https://en.dold.com/company/press-center/insulation-monitoring-in-dc-charging-stations-rn-5897-020.html

"What are the requirements of the standard? n ISO6469-3:2011 Electrically propelled road vehicles – Safety specifications – Part 3: Protection of persons against electric shock "the minimum insulation resistance of the on-board network must be maintained throughout the service life and under all operating conditions"."

http://www.bender.ro/aplicatii/documentatie_aplicatii/Emobility_PROSP_en.pdf

The common thread to all of the methods used are to prevent hazardous differential voltages from the person to the source,(or ground.)

The codes are usually created and reviewed by the underwriters(Insurance Companies) based on past experiences and claims.

There are many ways to tan a hide.

Each rule has it's particular design based on the locale and the engineers opinion o how to best comply,considering cost and effectiveness.

Codes are frequently revised due to differences on interpretation of the rules,and advances in technology.

Codes and rules are living documents,like languages that evolve over time.

British Standard 7671 covers it, Mildred.

"The current version is BS 7671:2018 (the 18th Edition) issued in 2018 and came into effect from 1 January 2019. ^[3][3] Amendment 1 to the 18th Edition was published in February 2020 but the only changes were to section 722 (Electric Vehicle Charging Installations). These changes came into immediate effect upon publication release, unlike previous amendments where 6 months elapsed before changes became compliant. ^[4] BS 7671 is also used as a national standard by Mauritius, St Lucia, Saint Vincent and the Grenadines, Sierra Leone, Sri Lanka, Trinidad and Tobago, Uganda, Cyprus, and several other countries, which base their wiring regulations on BS 7671."

https://en.wikipedia.org/wiki/BS_7671

Changes to Section 722

Section 722 (electric vehicle charging installations) provides requirements for the supplies to electric vehicles.

There are a number of significant changes in Section 722 of the DPC: Protection against electric shock Regulation 722.411.4.1 concerning the use of protective multiple earthing (PME) supply has changed. The exception for a dwelling if none of (i), (ii), or (iii) is reasonably practicable has been deleted. This now means that PME cannot be used unless you meet (i), or (ii), or (iii) of 722.411.4.1.

As a reminder of those regulations:

 Regulation 722.411.4.1(i) refers to a situation where a connecting point is supplied from a 3-phase installation used to supply loads other than charging points and where the load is sufficiently well balanced.

 Regulation 722.411.4.1(ii) requires a very low resistance earth electrode to mitigate the effects of an open circuit PEN conductor fault on the supply.

 Regulation 722.411.4.1(iii) refers to protection by a voltage operated device. An important change is that the regulation now makes the point that this device could be included within the charging equipment. It is worth noting that this device will also require an earth electrode.

The touch voltage threshold of 70 V mentioned in 722.411.4.1(i), 722.411.4.1(ii) and 722.411.4.1(iii) is on the basis that Table 2c (Ventricular fibrillation for alternating current 50/60 Hz) of IEC 60479-5{ed1.0} gives a value of 71 V for both-hands-to-feet, in water-wet conditions with medium contact area (12.5 cm2 ).

https://electrical.theiet.org/media/1154/the-impact-of-the-18th-edition-sections-722-753-and-new-730.pdf

"RCD protection Regulation 722.531.2.101 has been redrafted concerning RCD protection. The regulation now contains further requirements for both Type A and Type B RCDs to take account of DC fault current. "

https://www.proactivetechnicaltraining.co.uk/rcds-different-types/#:~:text=Type%20AC.,currents%20and%20smooth%20d.c.%20currents.

AP#1 could also have looked that up if arsed.

Yeah but what good would that do the rest of us...?

Using inductive coupling could eliminate a lot of the concerns with shock hazards,but this would affect the cost and profit of the vehicle,which will not fly with manufacturers.

Better to pass the cost on down to the end user,which is where all profit originates anyway.

That helps the economy.

Money is like electrons,nearly useless unless they are moving.

I don't mandate it. Who are you working for?

I appreciate all the answers provided here.

Thank you

Can you please tell me Is there a Particular logic for Mandating / Non Mandating.

Why such an expensive IMD needs to be used in the first case?

Liability...

No standard is <...Mandatory...>. However there are commercial, safety, insurance cover and possibly legal consequences for not following the applicable ones.

For an IT Earthing system is it mandatory to provide a Insulation monitoring Device (IMD)

What is the best earthing system for a DC fast charging Station

TN, TT, IT ?

https://myenergi.com/pen-protection/

British Standard 7671. Again.