Intermittent wipers, with wash wipe too !

[Lebro]

Circuit diagram added to above post.

Bob

[Keith Warren]

Hi Steve

Just picked up on this thread, I have a smart screen on my CP six and was caught out in the rain this week it was of no use at all, I know it’s cheeky but have you any of your kits left over?

great work you have done

Keith

[trchris]

Hi Keith

I bought one of Steve's intermittent wiper relay kits which I will not use as plans have changed on the tr6 it was for if you are interested let me know

Chris  

[Keith Warren]

Hi Chris

Sent a mail through I think, not done one for a long time, but would like to take you up on your offer.

Keith

[BlueTR3A-5EKT]

Years ago  I thought about searching for a kit and found this.

Have just found it again.  How does it compare?   Will it do a single speed Sidescreen car DR3  type wiper motor?

http://www.velleman.co.uk/contents/en-uk/p204.html

[RogerH]

Hi Pete,

that will do a simple Intermittent wipe very nicely.

The output relay will short the motor earth the ground at set times.

The timer control knob can be removed from the PCB and piggy backed on a long lead

 

Roger

[Lebro]

Well the very modified wiper delay unit (as at start of this thread) I used in my '3 had misbehaved once too often, so yesterday I pulled it to bits, & have now constructed a very simple one which works on any type of motor.

Circuit:

  FOR LATER LIVE SWITCHED MOTORS (later TR's)

   FOR EARTH SWITCHED MOTORS (TR2/3 etc)

The 1st version I found on the internet, the 2nd (lower) one is my interpretation configured for my TR3.

Once I found the best value to give a 5 second delay, I replaced the variable resistor with a 39K fixed one to improve relliabilty.

Had all the bits "in stock" so cost nothing to make, built it on a scrap bit of veroboard,

and mounted it inside the casing of the discarded Landrover delay unit !  then strapped to motor as before.

          

 

Bob

 

Edited November 9, 2022 by Lebro

[RogerH]

Nice one Bob

 

Roger

[Steves_TR6]

Good work Bob !

[Lebro]

Only slight oddity about this circuit is that when you switch it on there is a delay before the 1st wipe. Most do a wipe straight away. It's not a problem, just different !

Bob

[BlueTR3A-5EKT]

26 minutes ago, Lebro said:

Only slight oddity about this circuit is that when you switch it on there is a delay before the 1st wipe. Most do a wipe straight away. It's not a problem, just different !

Bob

Capacitor charging up?

[Lebro]

Yes, exactly. It's a very clever circuit. Uses the long charging time of the cap for the delay, & then when the circuit trips to start the wipers the charge in the cap keeps the 2nd transistor on for long enough to get the wiper moving.

Bob

[Ralph Whitaker]

Intermittent wipers were one of the things I missed when out in the TR this year. I didn1t really want to put any more switches  on the dash, but wondered if it would be possible to use a light switch instead of the wiper switch, so that first position (sidelights) would give intermittent wipe, and second position continuous wipe. That way I could put the "wiper" knob on the switch and it would look standard. Would a standard fixed delay relay work under that scenario as there are lots on ebay.

Ralph

[Lebro]

Ralph. That is exactly what I have done. It works well, you just need to run another wire from it to the wiper location.

Bob

[RobH]

19 minutes ago, Ralph Whitaker said:

Would a standard fixed delay relay work under that scenario as there are lots on ebay.

If you mean a ready-made wiper delay relay (rather than an actual 'delay relay' which is a specific electrical component) the answer is maybe.  It depends whether the relay contacts are wired to 12v. supply or or left 'floating', since an early car needs a contact which connects to earth while later cars need it to switch to supply. (as shown in Bob's schematics above).

A ready-made wiper delay unit probably has the relay configured for the first diagram, switching 12v to the wiper, which is how most wiper systems work and is fine for a TR6 with the 14W motor.   In order to use that on an earlier TR with the DR3-type motor it is necessary to modify the unit or to add another relay.  

For instance, this one cannot drive the early wiper motor, nor can it be modified easily :

https://www.12voltplanet.co.uk/12v-universal-intermittent-wiper-timer-relay-5-sec-delay.html

You would have to add another relay driven by this unit, so the contacts on the extra relay could be wired to earth as per Bob's second diagram. 

 

[Lebro]

If there is enough interest I could consider making a batch. Maybe get some printed circuit made.

Bob

[BlueTR3A-5EKT]

On 11/9/2022 at 5:55 PM, Lebro said:

Well the very modified wiper delay unit (as at start of this thread) I used in my '3 had misbehaved once too often, so yesterday I pulled it to bits, & have now constructed a very simple one which works on any type of motor.

Circuit:

  FOR LATER LIVE SWITCHED MOTORS (later TR's)

   FOR EARTH SWITCHED MOTORS (TR2/3 etc)

The 1st version I found on the internet, the 2nd (lower) one is my interpretation configured for my TR3.

Once I found the best value to give a 5 second delay, I replaced the variable resistor with a 39K fixed one to improve relliabilty.

Had all the bits "in stock" so cost nothing to make, built it on a scrap bit of veroboard,

and mounted it inside the casing of the discarded Landrover delay unit !  then strapped to motor as before.

          

 

Bob

 

Pedant time.

TR 2-3* had a CRT wiper motor fitted that gets power from the dash on/off control switch and the motor is connected to earth to make the circuit.  It has no self park

TR3*-4had DR3 /3A wiper motor single speed with self park.  The power started at the motor and the dash switch connected the earth circuit.plus motor earth for park

TR4A-5-250  DR3A two speed unit power starts at the motor and the switch connects either single or two wires to earth to make it go fast or slow. Plus a motor earth for park

TR6-8  14 W motor two speed and self park.  with power starting at switch fed by 4 wires. Plus a motor earth

[Lebro]

Now we know 

Bob.

[AlanG]

5 hours ago, Lebro said:

If there is enough interest I could consider making a batch. Maybe get some printed circuit made.

Bob

Hi Bob,

Please put me down for a 4A one.

Alan.

[Ralph Whitaker]

5 hours ago, Lebro said:

If there is enough interest I could consider making a batch. Maybe get some printed circuit made.

Bob

Thats a definite yes please from me Bob.

If using the light switch as stated does the intermittent relay stay on even when the wipers are switched to constant, in the same way the sidelights stay on when the headlights are selected.

I have the standard single speed with self-park.

Ralph

[PaulAnderson]

Bob,

I’d also be interested in one for a (two speed) TR4A motor but not sure how I’d switch it.  Will read the post from the beginning again and possibly other posts to recall it.

Paul

[Lebro]

On 11/11/2022 at 3:55 PM, Ralph Whitaker said:

Thats a definite yes please from me Bob.

If using the light switch as stated does the intermittent relay stay on even when the wipers are switched to constant, in the same way the sidelights stay on when the headlights are selected.

I have the standard single speed with self-park.

Ralph

Hi Ralph.  Yes the circuit remains powered up in both "on" positions of the switch, the 2nd position simply overrides the delay unit to give continuous wiping.

[Lebro]

On 11/11/2022 at 10:23 AM, BlueTR3A-5EKT said:

Pedant time.

TR 2-3* had a CRT wiper motor fitted that gets power from the dash on/off control switch and the motor is connected to earth to make the circuit.  It has no self park

TR3*-4had DR3 /3A wiper motor single speed with self park.  The power started at the motor and the dash switch connected the earth circuit.plus motor earth for park

TR4A-5-250  DR3A two speed unit power starts at the motor and the switch connects either single or two wires to earth to make it go fast or slow. Plus a motor earth for park

TR6-8  14 W motor two speed and self park.  with power starting at switch fed by 4 wires. Plus a motor earth

The circuit can be wired (or adapted) to work with all of the above except the CRT motor which has no self park.

1st step for anyone wanting to go this way would be to decide how to switch the circuit in. In the case of Tr3- 3A the simplest way is to obtain a light switch for the same car, & fit it in place of the normal wiper switch, then run the extra wire along the loom to the wiper motor location.

I am not familiar with the switch arrangements on the later cars, so some research needed there. 

Any circuits I make are likely to be mounted outside of a standard car type relay, not inside as mine is, so how to enclose / protect it needs to be considered.

Bob

[PaulAnderson]

Fuller details of the wiper motor types used in TR models is given in this helpful Post which for the TR4A shows

TR4A – DR3A 75568A – two speed (shaft & gear 54714897, 120 degree sweep)

and Tony T’s drawing on page two of this Forum page shows how the TR4A switch arrangement works

Paul

Edited November 14, 2022 by PaulAnderson

[Ralph Whitaker]

On 11/13/2022 at 12:35 PM, Lebro said:

 

Any circuits I make are likely to be mounted outside of a standard car type relay, not inside as mine is, so how to enclose / protect it needs to be considered.

Bob

Presumably it can be fitted in a protective box under the dash somewhere.

Ralph