Re: Very smoky XPT

[mauried@commslab.gov.au (Maurie Daly)]

In article <770uh8$bpu$1@metro.ucc.usyd.edu.au> matthew@mail.usyd.edu.au (Matthew Geier) writes:
>From: matthew@mail.usyd.edu.au (Matthew Geier)
>Subject: Re: Very smoky XPT
>Date: 7 Jan 1999 00:18:48 GMT

>In article <mauried.203.3693DEC6@commslab.gov.au>,
>Maurie Daly <mauried@commslab.gov.au> wrote:
>>
>>>>
>>> I dont know the exact values, but the HEP alternator is connected to
>>>the main engine shaft. The voltage and frequency to the train power line
>>>vary with engine speed. From 100v 25Hz to 300v 60+Hz or there abouts.
>>
>>Yes I suspected something like this , its a pity as it rules out using 
>>conventional 415 V 3 phase power for the cars if they have to be hauled by 
>>conventional locos with HEP , or using conventional power cars like PHGs/PHNs 
>>etc.

> 415v 50Hz is with in the range put out by the XPT HEP alternator set.
>Ive seen an adapter cable at Meeks Road that allows a standard railway
>powervan to power an XPT car. They also plug them into the normal 3 phase
>mains shore supply to power the cars when in the depot.

> The main difference is that the XPT has a real neutral in the train line,
>the traditional railway HEP supply doesnt.


Its not absolutely necesssary to have a neutral if the majority of the load is 
a 3 phase load, which would be the case if the air con uses 3 phase 
compressors or 3 phase motors driving conventional compressors.
You would need it though for 240 V single phase applications , if there wasnt 
an isolation transformer on the train somewhere.
Do the HEP sets in normal power vans provide 3 phase with neutral?

MD