CSR Wheelspeed Sensors no longer available

[David aka Blue7]

I have just heard that CC no longer supply wheelspeed sensors for the original CSR and all that is available is the sensor 2017 onwards and it seems that it is a similar situation with Redline.  I actually bought one as a spare back in 2018 thinking it was a direct replacement for my CSR but on looking closely the sensor looks quite different.

I don’t have a problem at present but thinking ahead, has anyone successfully fitted the 2017 sensor or modified it to work on a CSR?

The 2017 sensor is shown here ... out of stock of course

David

[Alan Reeves]

david if you run the same system, big ring and sensor, one would have thought they would be the same sensor part ?

mmm

[Geoff Brown]

Surely the sensor will be OK. Mounting, wiring & connector may be an issue ?

The important thing is the reluctor ring, the sensor 'counting' the teeth as it rotates expressing this into a signal for the speedometer.

Or is it more complicated an issue than that.

[David aka Blue7]

I haven't actually tried it so it may work but it looks different in that the end of the sensor is set much further back in it's housing.  I just wondered if anyone had fitted it as a replacement and if so did it function ok and did the mounting require any modification.

[ScottR400D]

Is the CSR different to the De Dion sensor, CAT-SP-0038AK? (Which of course is OOS but can be found elsewhere). 

[Jonathan Kay]

There's something about the source of the sensor in the archives. I'll try and find it when I get home.

Does anyone know the answer about which Sevens use the same sensors... that might become relevant.

Jonathan

[David aka Blue7]

Here is a photo of the two, the De Dion on the left has a part no. CAT-SP-0038AK and the CSR  sensor on the right had a part no. EMP40-1.  My impression is that the De Dion on the left would fit a narrower mounting and is supplied with a larger diameter mounting adaptor (shown above the sensor) into which it screws.  I just wanted to know if any CSR owners had fitted it successfully?

[Wrightpayne]

Have you read this thread - seems to have details of the manufacturer and alternate part no.

https://www.caterhamlotus7.club/forum/techtalk/speed-sensor-0

[David aka Blue7]

Thanks for the link to that discussion, I hadn't thought of looking at the part no. on the sensor and with the aid of a magnifying glass my part no. is slightly different XS508B1NAL2

The photo links no longer work and just show union jacks but I have made a note of the manufacturer Telemecanique.  A Google for the part leads to a company in Leeds Farnell and what look like the sensors with M8 width but they would need to be cut to length and connected to a suitable junction box.

A Google for my part no. finds them on Amazon at an eye watering price and at a better price at BPX Leicester

Thanks for the info, I have made a note of it

[Wrightpayne]

BPX have a pdf data sheet on their website for the part - maybe worth saving / printing a copy as seems to contain a lot of useful specification information.

Just up the road from me and where the MiL used to teach at the Primary School!
 

Ian

[Alan Reeves]

A call to Tony in CC parts will solve but my gut feeling is that all late cars have the same speedo sensor set up

and the latest one is very different but is a swop.

[CSR Phill]

I have fitted the new sensor to my CSR and with a bit of 'engineering' it does fit. It didn't solve my speedo problem [which reads zero all the time] but it does fit and pulses away fine with a 0.7mm gap. I sent the head unit to Speedy Cables who said it was duff, charged me almost the cost of a new one, returned it and it is still the same. Why are Caterham speedos so prone to failure?

[S_M]

Just bumping this thread in case anyone has a spare CSR speedo sensor/cable ?   Managed to break mine last night and seems the modern replacement is not in stock at Caterham ??

Cheers Sandy.

[Jonathan Kay]

Please can someone confirm which sensor works on a CSR.

Thanks

Jonathan

https://caterhamparts.co.uk/search?controller=search&orderby=position&orderway=desc&search_query=speedo+sensor&submit_search=

https://www.amazon.co.uk/Schneider-Electric-XS508B1NAL2-Proximity-Cylindrical/dp/B0028YTH3M

https://www.bpx.co.uk/store/product/xs508b1nal2

[David aka Blue7]

The part no. on my CSR sensor is  XS508B1NAL2 and I have made note of a link to a Telemecanique supplier Farnell here

I also seem to have made note of another similar Telemecanique sensor XS108B3NAL2 from Farnell here

In a previous BC discussion slightly different no’s are mentioned here
 

 

[S_M]

Does anyone know if the sensor has to be NPN output or can PNP output be used ?   Assuming anyone knows what i am on about 😇

[David aka Blue7]

5 minutes ago, S_M said:

Does anyone know if the sensor has to be NPN output or can PNP output be used ?   Assuming anyone knows what i am on about 😇

No, don't know what you're on about but here's a Google result

Both are used in various amplification and modulating circuits; the most frequent among its applications is being fully ON and OFF, which is referred to as switch mode. It's easy to remember that NPN stands for Negative-Positive-Negative and PNP stands for Positive-Negative-Positive.

I assume that PNP would be how horns are sometimes wired i.e. constant positive feed to the horn and the circuit is completed by pressing a switch that earths it?

[S_M]

9 minutes ago, David aka Blue7 said:

No, don't know what you're on about but here's a Google result

Both are used in various amplification and modulating circuits; the most frequent among its applications is being fully ON and OFF, which is referred to as switch mode. It's easy to remember that NPN stands for Negative-Positive-Negative and PNP stands for Positive-Negative-Positive.

I assume that PNP would be how horns are sometimes wired i.e. constant positive feed to the horn and the circuit is completed by pressing a switch that earths it?

I only ask as 1 of the sensors you link to ( the only one stocked anywhere ) XS508B1PAL is PNP output, but the correct original fitted one XS508B1NAL2 is NPN output.

Hope that makes sense......🤓

[David aka Blue7]

I see what you mean, the numbers are different, my sensor is XS508B1NAL2 and the link is to XS508B1PAL2 so I assume the N and P signify the difference.  I have looked at an explanation online by Schneider but I am still none the wiser and don't know i the P version will work on the CSR.  Maybe contact Farnell Tech Support and seek advice?  Have you tried Redline?

[Jonathan Kay]

NPN and PNP

Some speedometers, including some Caerbonts, can be wired to work with either type of sensor, eg:
https://www.smiths-instruments.co.uk/bespoke-projects/product-instructions/

But if only the wrong sort of sensor is available and the speedometer can't manage this then it wouldn't be too hard to add a bit of circuitry that would sort it out. 

Jonathan

[David aka Blue7]

Just to complicate matters further, the number I quoted above is the part number on my first 2008 CSR sensor, which had to be replaced.  I did have a spare which had a CC part no. CAT-SP-0038AK but last year a friend of mine required one urgently to get his CSR through an MOT so I sent it to him.  He subsequently ordered a replacement from CC and sent it to me.  However, it isn't the same as the one I sent to him, it is narrower maybe 4mm dia as compared to the one I sent to him which was 8mm dia.  Attached to the 4 mm dia. sensor is a plastic "spacer" for lack of a better description, which is 8 mm dia. and the 4 mm dia. sensor screws into it so that the assembled unit will slot into the location bracket.

Unfortunately there is no part no. on this sensor, there is a label on the lead with the following numbers 300A0019A, WO:522964, Date 25/03/22

HEADS UP!  CC have CAT-SP-0038AK in stock, the thinner with spacer version  here

Edited September 16, 2024 by David aka Blue7

[S_M]

Ok, sorry its taken me so long to update this thread. 

 I finally bought this sensor https://caterhamparts.co.uk/senders/6649-rear-wheel-speed-sensor-2017.html   

And this spacer bush specifically for the CSR. https://caterhamparts.co.uk/other/7168-sensor-bush-for-csr-speedo.html?search_query=speed+sensor&results=145

The CSR sensor mounting flange on the hub is an 8mm hole and the new sensor is 5mm diameter. Hence the CSR specific spacer bush which is 8mm outer diameter, sounds great but unfortunately the spacer bush inner diameter is only 4mm so you have to enlarge it to 5mm to allow the sensor to slide through it.  Easy enough to do in principle but its actually quite difficult without a suitable round chainsaw file..!!.     Also the new style sensor is only just long enough on the CSR.   But it works.

Thanks again to all the help. 

Sandy.

[David aka Blue7]

Thanks for the update but out of interest why didn't you buy the one I have as a spare shown in my link above and also shown here

https://caterhamparts.co.uk/senders/6707-rear-wheel-speed-sensor-kit-de-dion-cars.html?search_query=CAT-SP-0038AK&results=790

this one includes a bush that the sensor screws into?

[S_M]

1 hour ago, David aka Blue7 said:

Thanks for the update but out of interest why didn't you buy the one I have as a spare shown in my link above and also shown here

https://caterhamparts.co.uk/senders/6707-rear-wheel-speed-sensor-kit-de-dion-cars.html?search_query=CAT-SP-0038AK&results=790

this one includes a bush that the sensor screws into?

Good question.   The bush in that kit will make the hole through the hub too *thick*.   Which means that the 5mm diameter sensor will almost certainly not be allowed to get close enough to the toothed ring.   Hard to explain.  Hope it makes sence though....

[David aka Blue7]

1 hour ago, S_M said:

Good question.   The bush in that kit will make the hole through the hub too *thick*.   Which means that the 5mm diameter sensor will almost certainly not be allowed to get close enough to the toothed ring.   Hard to explain.  Hope it makes sence though....

When you say too "thick", do you mean too "long"?  Referring to the image below, could it be shortened by cutting along the line marked in red?