Newbie from NZ

Morning.!
Doody i want-(NEED) to protect these motors and electronics so thought i could use relays to protect each high amp motor circuit
would https://www.ebay.com.au/itm/MICTUNIN...frcectupt=true
something like this work ?
or this?https://www.trademe.co.nz/electronic...45063f2ae1-003

im not sure HOW large the amps-watts etc need to be but i just want to protect the electronics.
OR do i simply hardwire a 10-15-20 amp car fuse in the power supply feeds? this may be messier
trying to get smallest-neatest setup so i could fit them all in a protective case somewhere.
thanks if you can help
Richard

Richard,

I need to understand your thinking. How do you perceive a relay will protect the motor and/or electronics? A relay is effectively a switch, so my question is really what quality is actuating the switch? Are you talking thermal overload? (a thermistor somewhere in the speed controller?) Some form of limit control? (already accommodated with the motor speed controller)? Sorry, I don't understand where you're coming from for "protection".

Similarly the timer module that you have there. From the outset I'd argue a couple of points - that module is likely (from a glance at the image of the board) to fry with the current draw from your motor (and I'm only talking of the principal motor in this thread). And in terms of "protection" you're only looking to introduce a timed on-state with that, and the only protection this effectively offers is against prolonged use (the quality here being the probability of over-temperature of the power devices in the speed controller). That presupposes that particular failure mechanism.

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For the new controller and motor... tread with caution. If you use a long supply wire from the battery to the controller (increasing the resistance) you should introduce a level of protection that you can use to test, and then start to reduce in length as you gain confidence that the controller isn't overheating etc, with the motor under load. Ultimately you do want that cable length to introduce as low an electrical resistance as possible to allow you to attain the power through the motor that you expect

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This is what I recommended to avoid overheating. It's a heath-robinson solution but it's robust.

There is another potential failure mechanism of back-EMF from the PWM output to the motor frying the electronics (if poorly designed - pure speculation on my part) - which

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Have a read here... https://medium.com/jungletronics/dc-...f-589d8ed174cc, you might consider this a pragmatic approach

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was intended to address. Here, add one or three capacitors across the motor terminals, or (I prefer, but seems to have limited traction in a number of articles) a TVS to suppress the back EMF.

Hi
i guess im just trying to stop any of the electronics from frying. MY THOUGHT is that if i put relays in the switches( realize a relay is a low voltage switch) then it MAY stop the electronics getting zapped by to much V or Amps when switched on. Maybe im not heading in the right direction.
On my unit i have a 200W geared motor with a 60 Amp fwd-rev-speed controller
, a 120w geared motor with the 2 proximity switches with the 30A speed-reversing controller
and 10A linear actuator.
Non of these will be run simultaneously they will go in sequence so the current draw is lower.
the whole units in the boot of the vehicle so i imagined running a fairly decent sized awg feed direct from battery to the boot and feed of a contact there . ( lessening power drop)
Nothing runs for more than 40 secs at a time either...
being overly cautious perhaps but this is a prototype and i cant-dont want weak points that could cause returns -claims etc.
at the moment the battery is on the floor 1m away from the electronics but obviously when installed it would be feed off the car battery ( with motor running) which gives slightly higher V. and could possibly cause problems?? ( or not)
Thats really where i am. it will probably fine with a few inline fuses but i dont know .During trials ive never over stressed any motor or controller as when i fried the last one it costs $ to replace ( $ which are running out)
I do need to put pressure on all parts as who knows what the purchaser may stupidly do. It needs to be pretty foolproof.( or protected)
Cheers

Hi anyone?
im nearly sorted BUT i just have one ? .
i have the motors-then the controller box ( which determines -speed- direction-PSD switches etc)
i also have a 12v dc hand control pad and a 12vd control box. this is all very light wireing and even the outlet plugs are designed for simple light actuators.
How do i wire the controller into the circuitry ie the outlet from controller is small wires, even thought the hand controller activates relays in the controller box the outlet is small.
( controller box has max 60A over 3 circuits ) do i just stick fatter wires into the outlet?
Hope someone can understand
Doody you gave me a circuit diagram before but i think this is already in the controller box
Thanks

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Originally Posted by Doddy

I'm "thinking" that you're looking for an off-the-shelf solution, and there are such things readily available. For example.

https://www.amazon.com/uniquegoods-W...gateway&sr=8-1

All you need are two limit switches. The instruction manual (linked at the bottom of the page on Amazon) shows how to attach two NPN proximity switches (https://www.amazon.com/Twidec-Induct...s%2C204&sr=8-7 and from the photo that you provided in post 12, I'd simply drill two holes in the side-wall an inch or so above the moving sled, one at each end of travel, and fit the proximity sensors there; Add a short piece of angle steel attached to the bolts on the linear blocks (you show 8 bolts in the image) to project up to provide a moving vane to actuate the proximity sensors when the sled is in the two end positions.

Job done.

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Doddy
can you please help
ive installed 3 of the uniquegoods 30 amp controllers with npn switches each end
all works 100% BUT i want to get rid of the remotes and use a simple push button hand controller
ive wired this into the manual switch but i can only get it to work by using only 2 of the 4 wires. i think im grounding the circuit so infact closing the switch. trouble as soon as i release the button the motor stops ( with remote it stays ngaged until it hits the npn switch. is there a quick fix to turn this bit into a stay on system so when release the BUTTON it keeps moving until it hits the end then it reverses the direction. As said it works NOW with the remote as one press keeps it moving. Do i need to wire the handpiece differently or use the 2 other wires in the manual bit. ( says that using the manual makes the remote redundant but it doesnt do this . Any help cheers Richard

Post #34, #36 cover this.

You could develop a more cunning solution with an Arduino at low cost.

Hi
reread 34 & 36 and see where you have supplied a solution to the switches. the hand controller does work when i hold down the button but it seems to deactivate the npn sensors.ie keeps traveling past the limits as long as its held down.. i would of thought they would still kick in.
ive googled and found that what you have said is what i need ( convert a momentary switch into a toggle switch) again the unit has relays everywhere so would i need to install a complete new set of relays simply to achieve this function ( 2 x 3 units = 6 extra relays!)
I pulled the handset to pieces and it just has 6 microswitches which obviously need to be held down to complete the circuit.
your reference to Arduino again sort of worries me. i cant really see on their site how-what sort of system i would use to achieve what i need.I dont think im smart enough to work with this product.
anyway .....thanks .....

Do me a favour... measure the voltage, referenced to ground, of the two travel limit inputs, and similarly the voltage on the open/close inputs with reference to ground.

I’m trying to work out if you can directly couple a Logic device (typically 5v) to these inputs. The inputs are likely to float around either 12v or 5v (in the absence of an active switch input)

Hi
Mate i have no idea what you are asking
reference to ground , im just not that techy. im winging this on a hope and a prayer. i also dont have a voltage measurer.
i think im too much in the s..t to dig my way out
thanks for the help so far but i just cant get my head around how to do what you need . i really dont know where to go from here..............

Wonder on down to Mitre10, grab one of these:

https://www.mitre10.co.nz/shop/medal...range/p/464017

Its a must have if you're doing anything with electronics. Its like trying to cook without an oven otherwise.

Connect the black wire into the COM socket. Then the red wire into the V Ohm mA socket (like the picture). Turn the dial to Volts DC, range 20V (thats the area slightly counter clockwise from straight up).

Stick the black probe from the tester to a ground pin, or in the absence of a ground pin, stick it to anything big and bare metal that the electronics are connected to on the car. Stick the red probe from the tester onto each pin Doddy is talking about, it should give you some readings.