Tritium PKM150

[cafz]

Tritium's new PKM150 charger looks externally the same as the RTM75 that's been rolled out recently in a few places - it'll be hard to tell the difference when a new site is being built.

This one is modular, configurable as either 50kW, 100kW or 150kW, and has a HVDC interconnection between the chargers at a site.

 

[BCTS]

That's great that it'll likely be upgradable. It's just unfortunate that there isn't an easy way to get build bandwidth power to these sites.

 

[Hairyman]

Does anyone have any insight into the causes of the reliability problems with these chargers in general?

Some of it might be just perception - they are almost the only ones in the local market, so naturally it is a Tritium charger that falls over when a charger fails.

Some of it might be electricity network protection with very conservative settings arranged so that the default is to isolate the charger when there is any issue at all and so you get a lot of false positives.

Some of it might be problems with adequate wireless connectivity.

Some of it might be a relatively immature product and design issues.

 

[cafz]

Looks like the purpose of the HVDC interconnect is to share power over the site - so eg if you have a feeder capable of 300kW continuous, you can have two people charging at 150kW, 3 at 100kW each or 6 at 50kW.

 

[cafz]

Does anyone have any insight into the causes of the reliability problems with these chargers in general?

Some of it might be just perception - they are almost the only ones in the local market, so naturally it is a Tritium charger that falls over when a charger fails.

Some of it might be electricity network protection with very conservative settings arranged so that the default is to isolate the charger when there is any issue at all and so you get a lot of false positives.

Some of it might be problems with adequate wireless connectivity.

Some of it might be a relatively immature product and design issues.

Some I think might just be sites that get absolutely hammered - you will get failures more frequently with a higher duty cycle, and with no redundancy and seemingly long response/repair times, those failures stick out. Consider Mittagong NRMA - 9 check-ins on Plugshare in as many hours today, and since Plugshare typically only captures a fraction of the usage that site was likely going flat out all day.

 

[moa999]

On the webcast they said reliability was one of Tritium's selling points and they can fix 90% of errors within 30min remotely.

Now obviously local experience seems to differ but we don't really have other brands to compare to.

Certainly it seems sites often have unexpected issues initially (eg. Chargefox Shell Cove) but once fixed it seems better.
But also appears that parts supply is an issue.

 

[technerdx6000]

Minimum spec is 200A for these chargers. Thats only 70kW @350V (Model 3 nominal pack voltage). The optional higher 350A spec will give 122kW, so looks to be similar limitations as the PK350 where nobody can charge faster than 190kW on a 350kW charger.

 

[Craig 128]

Does anyone have any insight into the causes of the reliability problems with these chargers in general?

Chargefox has been transparent with some of their issues. This was from an email from Christmas Eve last year:

Sites and challenges​

Torquay, Euroa & Barnawartha
The ultra-rapid chargers had to be temporarily turned off due to a critical issue that affected Tesla Model X drivers. That issue has now been fixed after working closely with the manufacturer and all three of these sites are fully functioning again

Goulburn, Kings Meadows, Keith & Murray Bridge
Some of the chargers on these sites had communication issues due to a particular combination of modem and setup we use. That caused them to disconnect and become unavailable when connectivity dropped out. We’ve changed to a different setup during the holiday season that we know is more stable, but we’ll continue to monitor the situation.

Toombul, Ballarat, Ballina & Shell Cove
These ultra-rapid sites are technically very complex installations that need to be finely tuned. Some chargers can be sensitive to power setups and may occasionally fault with internal errors. Whilst sites can be powered up again, we’ve been replacing parts such as breakers and internal power supplies for more stable operation.

 

[cafz]

The Torquay, Euroa and Barnawartha ones mentioned are ABB.

 

[Hairyman]

Minimum spec is 200A for these chargers. Thats only 70kW @350V (Model 3 nominal pack voltage). The optional higher 350A spec will give 122kW, so looks to be similar limitations as the PK350 where nobody can charge faster than 190kW on a 350kW charger.

That is very interesting. I have had 187kW out of the ChargeFox charger in Zetland. It said 500A on the screen.

 

[doggy1]

I had 170kW at 22% SOC from the Goulburn 350kW Chargefox. Model 3LR (LG Pack).

 

[technerdx6000]

That is very interesting. I have had 187kW out of the ChargeFox charger in Zetland. It said 500A on the screen.

Yeah, that sounds right. 500A is the maximum the PK350 can output. As our packs are nominally 350V and 400V when fully charged, that gives a theoretical maximum of 200kW charge rate. 350kW is only possible with a 700V battery pack architecture or higher. So your Taycans with 800V and Lucids with 900V.

You'll notice the charge rate will start around 175-180kW on the PK350 and slowly creep up as the battery pack voltage rises. This occurs until about 33% state of charge after which the charge rate decreases to protect the battery.

Image of Tritium PK350 for reference

 

[Hairyman]

Yeah, that sounds right. 500A is the maximum the PK350 can output. As our packs are nominally 350V and 400V when fully charged, that gives a theoretical maximum of 200kW charge rate. 350kW is only possible with a 700V battery pack architecture or higher. So your Taycans with 800V and Lucids with 900V.

You'll notice the charge rate will start around 175-180kW on the PK350 and slowly creep up as the battery pack voltage rises. This occurs until about 33% state of charge after which the charge rate decreases to protect the battery.

Image of Tritium PK350 for reference

Thanks! Very informative

 

[Vostok]

Does anyone have any insight into the causes of the reliability problems with these chargers in general?

From this Chargefox “lessons learned” document, they claim that most faults are due to Software not Hardware. They said some chargers need weekly physical on-site visits to clear false alarms, something that should be fixable remotely. They also said they were concerned that critical high power components and vehicle connectors would be the most likely source of outages, but in practice that has not been the case.

Chargefox Lessons Learnt 4

This report is a summary of the lessons learnt by Chargefox for the whole project during the delivery of their Electric Vehicle Charging Network Project.

arena.gov.au