03 April 2010

Polar Pak

Following some discussion on a news group, I thought I would do a Blog on Polar Paks with NRC, and PN.

'Polar Paks' were introduced by National Rail to allow them to carry Reefer Container that required constant power between terminals/capital cities. The Polar Pac was a genset and fuel tank (supplied by Cummins Onan) and was like to be around 6-8kva, enough to powere about 3 x 20ft containers. The fuel tank looks to be about 100L.

Polar Paks have been installed on 3 main types of wagons, although none are in service as of 2010 and have been removed from the wagon.

5-pack well RQZY - No change to the code
60ft RQTY/RRDY - Converted to RRTY
60ft RQSY - Converted to RRSY


Taken in 2002 at Islington SA, an RQZY 5-pack well wagon has a Polar Pak fitted to the end platform section near the bar coupling. In this configuration, the Polar Pak could supply power to a container in the well which it is attached to, as well as the container to the left (over the bar coupling). As the wells were bar coupled, there was no need for plugs as the wagon could not be uncoupled. These RQZY wagons would have supplied power on the Melbourne to Perth corridor. Polar Paks on RQZY wells become quite uncommon by the mid 2005, as other methods were employed (RREY - see below).


Taken in 2006, an RRTY wagon is seen at Port Botany with a reefer container fitted on the deck. The close up photo shows the jumper connections on the end of the Polar Pak, allowing 3 reefer containers to be fitted on the deck of the wagon. THe RRTY wagons were common on the SeaTrain services between Port Botany NSW and Fishermans Island QLD. When this service ceased a few years ago, the RRTY wagons were placed into the general pool on Intermodal wagons. All Polar Paks have now been removed from these wagons as seen in an early Blog http://3.bp.blogspot.com/_Azj0TLmGrkA/S6NMHKT1ZwI/AAAAAAAAAD8/B8Wk9oDe02A/s1600-h/PS6y+(Large).jpg


Both photos were taken during 2007, when the RRSY wagons were not seeing as much use as in previous years. They were fitted with a Polar Pak at one end of an RQSY wagon in the early 2000s. The Polar Pak was secured to two steel beams across the wagon deck. Below the beams, the deck cut outs had been meshed in obviously so staff could start up the generators. With the Polar Pak on the deck, the wagon could only carry 2TEU, rather than the normal 3TEU, however, occasionally a reefer container would be placed on an adjacent wagon and the power cord safely run over the couplers.

The RRSY wagons were almost always captive on the Melbourne Brisbane services, and often ran as a pair, coupled together or close to each other in the train consist. Having read some NRC publicity material, it is believed that these wagons were set up to carry potato products originating in Ulverstone TAS, from Melbourne to Brisbane.


A newer concept to NRC was the Chiller Service, where 3 to 4 permanently coupled RQTY type wagons were recoded to RREY. The concept involved a large Generator (possibly 80kva) placed inside a 20ft container (see the grey container about 4 back in the photo) to act as the power source for all 4 wagons. The generator supplied power to a main line running through all wagons in the set. Each wagon had a 'jumper' cable to connect power between wagons. Each wagon then had a set of power outlets where containers could be plugged into.

The wagon sets were often used between Melbourne and Adelaide on the 'LandBridge' Patrick service, and also on the SeaTrain service (See RRTY). The photo above is actually a Brisbane to Melbourne service. Patrick marked containers were originally used on the Landbraige trains, however, grey NRC containers started to appear as the norm on all services.

This style of reefer connection (not using Polar Paks) has been used by PN/Freight Australia (in VIC on VExx type wagons), ARG (AEQY) and CFCLA (CQBY). QR probably do something similar also.



  1. I was going through my photo collection and came across a close up shot of the genset on a RQSY wagon:
    Pic 1
    Pic 1


  2. Nice shots Marcus!

    There are no longer any RRSY wagons in service - all have been returned to RQSY wagons and polac pacs removed.