DRS 37's and coach with pantograph?

[truckman060473]

Seen a shot on Youtube where top & tail DRS 37's work a yellow Network Rail coach with a pantograph. Is this for testing the 25Kv OHL for current / voltage accuracy or something?

 

[90019]

Sounds like Mentor.

There's some info about it here.

 

[rail-britain]

Mentor both monitors the electrical system between the overhead live wire and rail, and the actual mechanical line itself

The NMT also includes a similar coach
Mentor was downgraded for use on rural and interurban electrified routes

 

[truckman060473]

I'm not sure how fast any of the 67's are cleared to run, but I was wondering if they have been used on this test train to simulate the type of speeds an electric train would run under the wires?

 

[sprinterguy]

I'm not sure how fast any of the 67's are cleared to run, but I was wondering if they have been used on this test train to simulate the type of speeds an electric train would run under the wires?

The B4 bogies fitted to Mentor limit it to a maximum speed of 100mph in normal service, or potentially 110mph with some fettling and dispensation to run at this higher speed.

Mentors' predecessor, "Prometheus", which was cut up in 2007, was used during the late seventies and early eighties to develop the Brecknell Willis high speed pantograph. For these trials, the test car was sandwiched between two back to back HST power cars, or marshalled in an HST test formation, and operated at speeds of up to 125mph.

As is often the case, the excellent train-testing website offers some very useful information on this subject:

http://www.traintesting.com/Highspeed_pan.htm
http://www.traintesting.com/lab_6.htm

 

[MacCookie]

Mentor both monitors the electrical system between the overhead live wire and rail, and the actual mechanical line itself

The NMT also includes a similar coach
Mentor was downgraded for use on rural and interurban electrified routes

What did they do to downgrade it? When was this? Must have been recently, as it was still doing 100mph testing on the WCML over the summer.

Ewan

 

[mallard]

What did they do to downgrade it? When was this? Must have been recently, as it was still doing 100mph testing on the WCML over the summer.

I assume he means that the coach's role has been downgraded, rather than any
physical modifications.

I expect it's still used on the WCML when the NMT is required elsewhere/unavailable.

 

[Hydro]

MENTOR has not been downgraded at all, and has been as busy as ever. The NMT pan is rarely used due to being signed OOU due to non-calibration. It's been apparently fixed and re-calibrated, but still hasn't been used recently to my current knowledge. The NMT can still only test lines where the NMT obviously runs, so mainlines and a handful of secondary routes (soon to be a few less if it goes back to it's 2 weekly cycle, rather than it's current 13 week cycle), with MENTOR making up the balance. Currently MENTOR does the lot.

MENTOR will test up to 100mph, depending on train formation. Usual traction of favour at the moment is 37's, 67's have been seen on it on rare occasion.

It measures all physical contact forces and mechanical interaction of pan and wire using an instrument BW high speed pantograph. It draw no current whatsoever, and is completely electrically isolated from the coach. To achieve full isolation, transmission of the telemetry is via light pulses down a fibreglass tube. The telemetry is powered by batteries which are charged via a small wind turbine (of variable effectiveness) and which are changed every time the coach is in Derby. We used to have to go on the roof to change them when off the wires, but H&S put paid to that.

MENTOR is due a full overhaul in the coming year, with the pan moved to the other end of the coach (where the Stone-Faiveley pan used to sit when it had one), a corridor connection put in at the current pantograph end, and a full replacement of the telemetry system, which is largely original from the 70's. The telemetry system is quirky and drifts out of calibration quite easily, which necessitates the pan being dropped and multimeters and twiddly tools being used to quickly reset all telemetry voltage readings to zero. It's quite fun to use, in a geeky way.