BEP TS1 Tank Sender - Checking Resistance

[BigAl.NZ]

Hiya

I have a BEP TS1 Ultrasonic Tank sender that I want to work with my new VDO SingleViu gauges (0-180 Ohm).

The sender has 3 wires (+/- and sender) so I connected the sender up and powered it all up, but the gauge didn't move.

So I took the sender home and spoke to BEP to check that I could power the sender up using a bench power supply (12v) and also 12v on the sender wire, then measure the resistance across neg and the sender wire.

BEP stated this test they have also tried, but it doesn't work as a test, and that I would just read 0 Ohms - no matter what distance the sender is from a surface/liquid.

This is exactly what happened, I powered the sender up and just got 0 Ohms.

I cant work out whether (1) as BEP say this is not a valid way to test the sender or (2) the sender doesn't work the way the gauges expects and the 0 Ohms is the reason that the gauge needle doesn't move from 0 Ohms.

I am certain the gauge is set to 0-180 Ohm because the old resistive sender from WEMA I still have and it has 0-180 printed on it and the gauge was reading ok with that sender, so gauge is working and set to work on that scale.

Hoping someone familiar with BEP TS1 might be able to jump in here and explain what I am missing?

[Wotname]

OK, I am not familiar with the BEP TS1 but I do sorta know enough about gauges and senders in general to be dangerous

The very first thing to know is what the TS1 has been programmed to output. Reading the BEP literature, it seems you have four choices - 1. 0-5V, 2. 10-180R, 3. 10-300R and 4. 20-33R. Only when you know what output it has been programmed for can you make a meaningful test.

Assuming the sender is programmed for one of the three resistance scales, you can't put 12V on the sender wire (green) and expect to read ohms between the sender wire and the -ve wire. I would be expecting to see ohms between an open circuit sender wire and the -ve wire.

If the sender has been programmed to for 0-5V output, I would be expecting some volts to be seen between an open circuit sender wire and the -ve wire.

Of course, all tests need to have the sender powered up with 12V on the red wire.

[BigAl.NZ]

I tried with 12 applied to the power wires and nothing on sender wire then measured Ohms across neg wire and green sender wire.....nothing. (But I do hear the clicking of the relay or something inside sending out the ultrasonic signal)

[Wotname]

Originally Posted by BigAl.NZ

I tried with 12 applied to the power wires and nothing on sender wire then measured Ohms across neg wire and green sender wire.....nothing. (But I do hear the clicking of the relay or something inside sending out the ultrasonic signal)

This is good - see more below.

Also I have read somewhere on the BEP literature that shorting the green wire to the -ve does bad things to the TS1.

Anyhow here are my current thoughts.

After lying awake most of the night thinking about the TS1, I have some more thoughts - OK, I didn’t’t stay awake all night but I did give it some more thought.

Given it’s digital nature, it won’t be easy to test bench the TS1 at home by using old analogue technology.

So how do we test the issue? I am presuming the issue is - it doesn’t work when connected the your existing VDO gauge.

We know the VDO SingleViu gauge works with the 10-180R WEMA sender but this doesn’t prove the VDO SingleViu gauge is an old style resistive analogue gauge. The VDO might be a digital style gauge with a ‘analogue lookalike’ stepper motor pointer. It does look like a stepper drive pointer on my mate's VDO SingleViu tank gauge (using a 10-180R WEMA sender). We also know the TS1 does not work with digital gauges. So are the TS1 and the VDO gauge compatible? I don’t know for sure one way or the other. I would be asking your VDO gauge supplier for guidance here. I believe it was NAMIISS, if so I would trust their advice.

Assuming they are compatible then I would proceed this way. Every thing below is predicated on the confirmation of them being compatible.

Reconnect the WEEMA sender to prove the wiring and gauge are still OK.

Assuming they are, then something about the TSI is faulty . Is it the unit or the installation?

Now for my thoughts on testing the TSI unit (not the installation) - remember this is mostly theory, I haven’t seen a TS1 up close and dirty.

The TS1 is essentially a digital ultrasonic device with programmable outputs. The easiest output to test is the 0-5V output. If you have your own programer, I would re-program it to the 0-5V and try to bench test that arrangement.

The TS1 has at least three sections. A ultrasonic transmitter (and receiver), a programmable convertor to determine the level and an output driver stage.

To test the programmable convertor and output driver stage, ensure the output is programmed to 10-180R. Reconnect it to the existing gauge, ensure the ultrasonic transmitter can not detect a valid fuel level (eg shield it or point it to something impossible for it to read). Now leave it this way for more than 10 minutes (say 15 minutes). After 10+ mins of an invalid level, the convertor should swing the output repeatedly from 10R to 180R so the gauge should repeatedly swing from full to empty. This test does not prove the transmitter/receiver but will prove the programmable convertor and output driver.

If you can’t read the programme or re-programme the TS1 with the programmer, then the output driver is likely to be faulty.

Can you test the ultrasonic transmitter/receiver? Well, sort of; in a bush technicians way. The transmitter should pulse - probably around 20 or 30 KHz. While this is above normal hearing, sometimes you can hear sub-harmonics of the transmissions. A sort of clicking noise. It is especially easy to hear if you place the transmitter hard against the bone immediately behind your ear. While this probably not recommended, I would try it - briefly. FWIW, the ultrasonic pingers on aviation flight recorders can be tested this way. In the case of the TS1, if you can hear the clicking, most likely the transmitter is working. If you can’t hear it, you are none the wiser.

Dunno if any of the above will help or not but ATM, I’m out of other ideas apart from getting hold of a known good TS1.

[BigAl.NZ]

Originally Posted by Wotname

This is good - see more below.

We know the VDO SingleViu gauge works with the 10-180R WEMA sender but this doesn’t prove the VDO SingleViu gauge is an old style resistive analogue gauge. The VDO might be a digital style gauge with a ‘analogue lookalike’ stepper motor pointer. It does look like a stepper drive pointer on my mate's VDO SingleViu tank gauge (using a 10-180R WEMA sender). We also know the TS1 does not work with digital gauges. So are the TS1 and the VDO gauge compatible? I don’t know for sure one way or the other. I would be asking your VDO gauge supplier for guidance here. I believe it was NAMIISS, if so I would trust their advice.

The TS1 is not on the list of tested and supported hardware by VDO - perhaps I am overly optimistic they should work together - I figured hey if it works on the principle of measuring resistance then they should work. Maybe this is wrong.

Originally Posted by Wotname

This is good - see more below.
Reconnect the WEEMA sender to prove the wiring and gauge are still OK.

Assuming they are, then something about the TSI is faulty . Is it the unit or the installation?

Now for my thoughts on testing the TSI unit (not the installation) - remember this is mostly theory, I haven’t seen a TS1 up close and dirty.

The TS1 is essentially a digital ultrasonic device with programmable outputs. The easiest output to test is the 0-5V output. If you have your own programer, I would re-program it to the 0-5V and try to bench test that arrangement.

The TS1 has at least three sections. A ultrasonic transmitter (and receiver), a programmable convertor to determine the level and an output driver stage.

To test the programmable convertor and output driver stage, ensure the output is programmed to 10-180R. Reconnect it to the existing gauge, ensure the ultrasonic transmitter can not detect a valid fuel level (eg shield it or point it to something impossible for it to read). Now leave it this way for more than 10 minutes (say 15 minutes). After 10+ mins of an invalid level, the convertor should swing the output repeatedly from 10R to 180R so the gauge should repeatedly swing from full to empty. This test does not prove the transmitter/receiver but will prove the programmable convertor and output driver.

The 0-5v test is a good idea. Interesting BEP suggested testing it this way too, since they have not have luck testing using the resistive method.

I have my really old tank gauges that the VDO's replaced, so I think I might test the TS1 with a old (think 90s) style gauge - then I confirm that the TS1 is ok, and that the new VDO is ok - and it becomes a issue of compatibility.

Will let you know.

[Wotname]

Originally Posted by BigAl.NZ

The TS1 is not on the list of tested and supported hardware by VDO - perhaps I am overly optimistic they should work together - I figured hey if it works on the principle of measuring resistance then they should work. Maybe this is wrong.

Starting to look this way!

The 0-5v test is a good idea. Interesting BEP suggested testing it this way too, since they have not have luck testing using the resistive method.

Hey, they are as smart (or dumb) as me!

I have my really old tank gauges that the VDO's replaced, so I think I might test the TS1 with a old (think 90s) style gauge - then I confirm that the TS1 is ok, and that the new VDO is ok - and it becomes a issue of compatibility.

Absolutely excellent idea

Will let you know.

Looking forward to hearing more .

[BigAl.NZ]

By the way - namiss while cheap are not great at support.

[Wotname]

Originally Posted by BigAl.NZ

By the way - namiss while cheap are not great at support.

Good to know, thanks. I must have been lucky so far.

[BigAl.NZ]

I have had a couple of people now say the best thing for the TS1 (because they have tried them) is to put it a bucked with sinkers!!

I could not get it to work with my old VDO gauge either, but will do some more tests later.

[Squanderbucks]

You can’t test or calibrate these trying to measure ohms. You can measure the volts but the ohms range is worked out internal to the gauges. The gauge sends a “pull up” voltage to the sender and returns a calibrated voltage that the gauge reads and converts.
You have to purchase gauges and senders with matched ranges and pull up voltages. Some are fairly standard and other custom. There is no home conversions possible.
You just need to either change your sender to one that matches your gauge or get a matching gauge that the manufacturer says works with theirs. LOL

[BigAl.NZ]

Originally Posted by Squanderbucks

You can’t test or calibrate these trying to measure ohms. You can measure the volts but the ohms range is worked out internal to the gauges. The gauge sends a “pull up” voltage to the sender and returns a calibrated voltage that the gauge reads and converts.
You have to purchase gauges and senders with matched ranges and pull up voltages. Some are fairly standard and other custom. There is no home conversions possible.
You just need to either change your sender to one that matches your gauge or get a matching gauge that the manufacturer says works with theirs. LOL

Gauges = 0-180 Ohms
Sender = 0-180 Ohms

They match!

So I should be able to measure a differing voltage as I move sender up/down?

[Squanderbucks]

I have CruzPro gauges that allow user custom calibrations but these are not for the faint of heart. Had to have custom senders made by Centroid company because the CruzPro required a unique 3 volt pull up. User measures the voltage after adding each of 32 fuel increments to the tank and inputting that into a in app spreadsheet. You have to calculate the Ohms using their formula for each value and assign the proper gallons to each value. Then upload through the app via serial connection to the gauge. Whew. Yes it can be done and I have done this routine several times when lightening made me replace everything.
Bottom line. Buy known approved matched sets unless they are made for your calibration like my CruzPro’s.

[Squanderbucks]

I have seen testing procedures outlined where a pvc pipe with end caps is used to test various levels of fluid. Close off the bottom. Mount the gauge through the top and fill to various levels through a fill hole. Check and see if 0 -1/4 -1/2 -3/4 - F appears about correct.

[BigAl.NZ]

Well I took an old gauge (VDO 90s era) and the sender to BEP. They were very helpful - tested the sender and found it was faulty in resistive mode and gave me a new one. Cant fault that.

[Wotname]

That's a good start!

I suppose you haven't had a chance yet to try it with new VDO gauge?

Maybe (????) connecting it to the new VDO gauge kills the sender - you will soon know!!!!!