please help me on this one please  i apologise for the noob question 

 

i am in the process of attempting to illuminate my child bike trailer just in case me and my daughter get caught out at dusk plus for darker nights during winter

 

my thoughts are using led strips red coloured for the rear 

 

kind of like these not the actual ones but the first picture on ebay

 

now this i where i get stuck i want to create two vertical pieces down the back of the trailer with one horizontal piece across the bottom but i dont know which connectors i would need 

 

next problem i have is power should i use a battery box with 10 aa batteries in or would you recommend a lithium rechargable pack but i dont know which one 

 

i understand i am asking for a lot of help on this but i havent a clue on what to order 

 

 

help and pointers really really appreciated

I had some LEDs that are 12v but work fine from a 9v PP3 battery. Ive still not got around to doing the little project yet but see the photo. There are 48 LEDs in total and they seem bright enough. Not sure how long the battery would last as, like I said, I've not got around to putting it all together yet.

 

 

I was was going to solder the tails together to a PP3 battery clip and away I go. Not quite what your doing but I was planning on sewing the strips to the material as there is a depression between each LED on the strips I bought to prevent them sliding down.

 

hope this helps a little.

Edited 21 April, 20179 yr by andy-fisher

Thinking a lithium ion pack would give good power just not sure which connectors to the led strip would work 

Seen a few of these on Amazon that are usb plug and play 

Would a power Bank work on these ?? 

 

If can a multi usb plug be used to attach multiple sets ??? 

Id have thought you could use a power bank for the USB LEDs with no problem. Use a USB splitter to power multiple strips.

 

ive not tried it before though so don't know for sure how many strips a power bank would provide power for. Depends upon the current draw of each strip and which power bank you get. Some provide 1A and some 2.1A. LEDs are a low current draw but the more you add the more current you will need. (V=IR) I presume the power bank will be 5v so you have 1/3 of the equation. 5=IR. Just need to know the total resistance of the strips you wish to add and you will be able to work out the current you will need to power them.

 

Have you thought about just adding some normal rear bike lights to the trailer though or is there nowhere to mount them to?

Edited 22 April, 20179 yr by andy-fisher

10 AAs in series will theoretically give you 15v which is a bit high. 

 

I have 2 50cm led strips (I bought 4 but didn't need the extra light so went for 2 to save battery) powered from a battery box with 8 AAs in my shed and I reckon a standard alkaline set of AAs should have a running time of about 3-6 hours (I don't know what the active voltage of the LEDs are). 

 

Wired into a double pole light switch with an extension cord it works very well.  Although I also made sure to get a battery box with an off switch as well. 

 

The led strips plug into each other with barrell connectors come with a power connector to solder to a power supply although I just cut the denial end off the extension cable and wired it directly through the switch. 

 

On the photos the black box box above the light switch is the battery box. 

 

Battery box

https://www.ebay.co.uk/itm/301821735594 

 

 

4x LED strips

https://www.ebay.co.uk/itm/272551103772 

 

Extension cable

https://www.amazon.co.uk/gp/aw/d/B01MET8QW/ref=ya_aw_oh_bia_dp?ie=UTF8&psc=1

Edited 22 April, 20179 yr by gullyg

Excellent thank you 

3 hours ago, gullyg said:

10 AAs in series will theoretically give you 15v which is a bit high. 

 

I have 2 50cm led strips (I bought 4 but didn't need the extra light so went for 2 to save battery) powered from a battery box with 8 AAs in my shed and I reckon a standard alkaline set of AAs should have a running time of about 3-6 hours (I don't know what the active voltage of the LEDs are). 

 

Wired into a double pole light switch with an extension cord it works very well.  Although I also made sure to get a battery box with an off switch as well. 

 

The led strips plug into each other with barrell connectors come with a power connector to solder to a power supply although I just cut the denial end off the extension cable and wired it directly through the switch. 

 

On the photos the black box box above the light switch is the battery box. 

 

Battery box

https://www.ebay.co.uk/itm/301821735594 

 

 

4x LED strips

https://www.ebay.co.uk/itm/272551103772 

 

Extension cable

https://www.amazon.co.uk/gp/aw/d/B01MET8QW/ref=ya_aw_oh_bia_dp?ie=UTF8&psc=1

 

First 2 links are over 90 days old 

 

Do you have the seller name instead 

it might be simplest to do it using USB as above. If you're happy to muck around - maybe if you enjoy mucking around - and want the absolute best battery life then you could probably connect directly to the pins for common and red with a battery pack. At least the strip I've got on the back of my tv has 4 pins: common ( maybe +12 or earth i can't remember), red, green and blue.

If you really want/need 12v, could you use a single gel car battery, or 2x6v motorcycle ones in series with each other? I used to get over 1hr from a battery electric mower using 2 motorcycle batteries to drive the motor.

Think I'm sorted now

I have. 6800 may 12 V powerbank coming and two 50cm red led strips not sure how long the power will last but we'll see 

Main problem areas IMHO are

are individual LED strips rated at 12v ( or the voltage drop across one given voltage across one x number of lamps), so you can workout if the set will take 12v or not light.

Do you know the capacity of the battery and the current drain.

I'd also look at the weight ,and how well you can secure the battery .

If you don't know, LEDS (= Light emmitting diodes) ,which are semiconductors, so if connections are reversed , the lights won't come on and may even damage the lamps.

What you can do ,is if the LEDS are too bright and run down the battery early is to work out the current  of if it's given and work out the value of resistor  to be placed in line with the feed.

If that's what you've got in mind- ask and I( or another electronics bloke) will tell you how.

 

Power pack is rated at 6800 mah 

 

Lamps IL probably will only use 1-2 strips 

 

Look at this on eBay http://www.ebay.co.uk/itm/151889463531

Looks like no probs ,so you'll not have to get calculator out and get to grips with OHMS law. Most LED run around 10-20 mA  and that power pack will stick out

6000- so it shouldn't get warm. Even it they're wired in series my calculations at 20 mA show draw at 1A.

(Two ways of wiring them - series, where it's similar to a group holding hands. One fails, all go out, or parallel where they're all hugging, and if one goes out, then only that one fails).

 

 

However - if daughter is wearing a helmet- then I'd suggest a red flasher on the rear, and a white on the front.

She will be sat in trailer with the roof up she will have a helmet on and tbh these lights have turned up and probably won't be using them in that project i will attach some additional normal bike lighting and use these LEDs in the shed 

 

Thank you for your help though 

I didn't quite understand where you've got to with this. But if it helps I've got 70 cm of rgb strip left over from the back side of my tv, with a connector on one end. If you want to send me a stamped addressed envelope it's yours.

3 minutes ago, wonkyewok said:

I didn't quite understand where you've got to with this. But if it helps I've got 70 cm of rgb strip left over from the back side of my tv, with a connector on one end. If you want to send me a stamped addressed envelope it's yours.

Thanks for the offer 

 

Just to be clear it's was destined to go on the back of a child bike trailer for when dark nights come so it can be seen on the short section of unlit road from our village to the next before we join a cycle path