ETS on mk1 coaches?

[truckman060473]

a faded memory of my dad taking my grandparents to Carmarthen station circa 1980 - 1983 for their trip back to Llanelli after coming down for a visit brings up a query. it's the 20.50 ish departing, BR blue class 47 hauled mail train + mk1 coach stock (08 shunter used to put the mail vans on front of train while the 47 run round). i used to come along to see them leave, and used to nose around the corridors they had at the time, while it was in the station. i remember the dimly lit bulbs in the coach compartment. i can also remember seeing a generator of some sort under the coaches driven by a flat belt from the wheelset. i just wonder what the function of these was considering there was dim light in the coach when the train was stationary. when the class 47 did the run round, i.e. disconnected from stock, would the coach lights be working? and if so from what source? i can't remember.

 

[Old Timer]

Each vehicle had a large battery box underneath, which was charged by a dynamo, which the belt you saw drove. When the train was running there was sufficient power to charge the batteries ands run the vehicle lights, when the train was stationary power was drawn from the batteries, hence the flickering that could be seen on starting and stopping, and the slightly dimmer lighting when at a stand.

 

[ChrisCooper]

The belt driven generators on the Mk1s were used to provide power for lighting going back to the days of steam heating. They charged batteries, so power would be available for lights when the train was stationary. The same basic system was also used on pre-nationalisation and pre-grouping stock with electric lights. A lot of Mk1s were fitted with dual heat, able to work with steam heat or ETS, but the generators still provided power for lighting, as this was 24v wheras ETS is 800v. On the air-conditioned Mk2s, Mk3s and Mk4s, ETS powers a motor-generator/static converter on each coach which gives both 3 phase for air conditioning and 24v DC for lighting, but batteries are still provided so the lights stay on when there is no train supply from the loco.

 

[truckman060473]

yes interesting. so for example, a winter steam charter in modern days, does it need to use these mk1's for their compatibility for steam heating (correct me if i'm mixing up things here) so the loco can heat the coaches?

 

[87015]

yes interesting. so for example, a winter steam charter in modern days, does it need to use these mk1's for their compatibility for steam heating (correct me if i'm mixing up things here) so the loco can heat the coaches?

Mk1s (or early Mk2z) stock needs to be used more for it being vacuum brake more than for steam heat, most tours seem to have diesel (WCRC) or genny van (EWS) for ETHing purposes although some is still steamed I think. The Jacobite is steam heated when cooler mornings require it for one.

 

[truckman060473]

what about the double headed "hall" class steam train back from Didcot on 20th Feb - is there any method of heating the 10 or so mk1's (i assume) that were behind it? quite a cold day and no diesel loco involved here for heat purposes

 

[matt]

The steam loco would have provided steam heat for the mark 1s and 2s as all of the tyseley stock is dual heated

 

[royaloak]

ETH (now ETS) is 1000V, except on the southern where it was 750V.

 

[Moog_1984]

ETH (now ETS) is 1000V, except on the southern where it was 750V.

I thought it was 430V , but that was "trams" (HST's ) apparently. It was 400 to 600 amps, quite a whack. Indexing was calculated on kwh: lowest was 34 or the like for 33s' and 37/4s IIRRC?

The 3 class 25 based ETHELS were index 66 (330kw) as were the other 169 ETHELS aka 31/4s

Maybe "going green" will see a move away from air-conned stock ....roll on mark IIs ...

 

[royaloak]

The HSTs have a 3 phase supply.

 

[D6975]

I thought it was 430V , but that was "trams" (HST's ) apparently. It was 400 to 600 amps, quite a whack. Indexing was calculated on kwh: lowest was 34 or the like for 33s' and 37/4s IIRRC?

The 3 class 25 based ETHELS were index 66 (330kw) as were the other 169 ETHELS aka 31/4s

Maybe "going green" will see a move away from air-conned stock ....roll on mark IIs ...

How many 31/4s????
I only remember there being 70, and even then, not all at the same time.