What are JB4 ports?

[NicKarla]

I went to Oldfieldelectrical and they had exactly what I needed. A 30w 12v driver with bare wire terminals for my old 6 way connector to connect to. All is working perfectly now.
Thanks for everyone’s help.

 

[flameport]

If I may ask, is there a limit on lead length to the light,

Only due to volt drop, but with LEDs using a tiny fraction of the current compared to halogen, it's usually insignificant.

Some of the older drivers for halogens had a limit due to the capacitance of the output wires and limits on radio interference, but that only applied because the output was high frequency AC. Not applicable with DC.

 

[NicKarla]

https://www.screwfix.com/p/aurora-12-240v-constant-voltage-led-driver-16w/2107t#_=p

Tooltation proberly do similar.
I assume your lamps are 12 volt just make sure its labelled CONSTANT VOLTAGE 12 VOLT.
look for a removable cover on the end, you will see Flameports is similar.
you can load this up to 15 watt total lamps.
Its unlikely you will get more than 2 wires in the output terminals so if there many lamps, you will need to wire out to a JB as Flameport suggests,
If thats the case you can get the Toolstation sensio ones and cut the JB4 box off
https://www.toolstation.com/sensio-led-driver/p13514
Though looks like Toolstation are phasing them out.
What is the total wattage you need

You mention a Plan B Existing Distribution box, you could likely repurpose this by cutting the input lead and connecting into the driver.
Are you sure that plan B box is not using the same Jb4 plugs you mention

I had a look at the JB4 connections boxes in Toolstation. You would have to have the correct connection to fit. No idea why they are selling this as no one seems to have JB4 connectors unless you buy all new lights, cables etc with them on. Crazy, just buy a bare wire one that you mentioned. In the end I went with a 30w 12v Oldfields one similar to the Screwfix one you mentioned but only £3 more and looks well made.