Spend half an hour at the SED trade counter and youâll hear the same kind of questions again and again.
Some are quick: âGot any more of these?â Others need a bit more digging: âWill this work with that?â
or âWhat size cable do I need for this job?â
We thought weâd pull together ten of the most common questions we get asked â and how we usually help.
Itâs not a replacement for proper design or the Wiring Regs (that part is always down to the electrician),
but it does show how we try to back you up day to day.
1. âWhat size cable do I need for this?â
This one comes up a lot â and the honest answer is: it depends.
Weâll always remind people that final design and compliance with the regs is the installerâs responsibility.
But we can help you think it through by asking things like:
- Whatâs the load and how far are you running it?
- How is the cable being installed â clipped direct, in insulation, underground?
- Is this a new circuit or an alteration?
Once weâve got a rough picture, we can point you towards suitable cable types and sizes to match what youâve
already calculated, and make sure youâve got the right glands, fixings and accessories to go with it.
2. âIs this the right LED to replace my old fitting?â
Another regular: someone walks in with a lamp or a photo of an old fitting and asks what LED they should use instead.
Weâll usually look at:
- Cap type (GU10, E27, etc.)
- Wattage and lumen output on the old lamp
- Colour temperature â do they want warm, cool or daylight?
- Dimming â is it on a dimmer or just on/off?
From there, we can suggest LED options that keep the look and feel the client wants, while using less energy and lasting longer.
If itâs a fluorescent-to-LED panel or batten swap, weâll talk about light levels and spacing as well.
3. âWhat IP rating do I need here?â
IP ratings can be confusing, especially for bathrooms and outdoor areas.
We often get questions like:
- âIs IP44 enough for this?â
- âDo I need IP65 over a shower?â
- âWhat would you use outside on a coastal property?â
Weâll talk through where the fitting is going, how exposed it is to water, dust and the elements,
and then suggest suitable IP ratings and products. You still make the final call, but we can help narrow the choices
so youâre not guessing off the shelf.
4. âWill this MCB/RCBO fit that board?â
Boards and breakers are another common one.
Very often, someone will hold up a device and say: âWill this fit my board?â or
âHave you got the equivalent in [brand]?â
Weâll check:
- The make and model of the existing board
- The type and rating of the device you need
- Whether thereâs a manufacturer-approved equivalent
Where possible, weâll match like-for-like from the same manufacturer. If thatâs not an option,
weâll talk you through whatâs available so you can make an informed decision and keep things compliant.
5. âDo I need fire-rated downlights here?â
This comes up a lot on domestic and small commercial jobs.
Weâll usually ask:
- What type of ceiling is it?
- Is there a room above?
- Is it a conversion, extension or new build?
We can then point you towards suitable fire-rated downlights, bezels and lamps where theyâre needed,
and explain the difference between integrated and non-integrated options so you can choose what suits the job
and your client best.
6. âWill these lights work on a dimmer?â
Dimming can be a minefield if youâre mixing older dimmers with newer LED fittings.
Typical questions include:
- âCan I put these on the existing dimmer?â
- âDo I need a special LED dimmer?â
- âWhy is it flickering?â
Weâll check compatibility info from the manufacturer, talk about leading-edge vs trailing-edge dimmers,
and suggest dimmers and lamps we know play nicely together. That way youâre less likely to get the
âitâs buzzing / flickeringâ phone call later.
7. âCan I use this outside / in a garage / in a loft?â
Plenty of jobs involve spaces that are cold, damp, dusty or just awkward.
Weâll ask where the fitting or equipment is going, what itâs exposed to, and how itâs going to be used.
Then weâll suggest:
- Appropriate IP and IK ratings
- Suitable housings, enclosures or bulkheads
- Cable types and accessories that can cope with the environment
Itâs all about matching the gear to the conditions so youâre not back in six months swapping out failed fittings.
8. âCan I mix brands on accessories and plates?â
Grid systems, decorative fronts and accessories are another common area of confusion.
We get questions like:
- âWill this front fit that grid?â
- âCan I use another brandâs module in this plate?â
In most cases, grid and plates are designed to work within the same brand family. Weâll check the catalogues,
look at what youâve brought in, and help you find combinations that are designed to go together so you donât
end up with something that doesnât quite fit â or looks wrong on the wall.
9. âHave you got something a bit cheaper that will still do the job?â
Budgets are tight. Itâs very common to hear: âHave you got a cheaper option?â or
âClientâs getting nervous about the price.â
Weâll always be honest about what youâre trading off:
- Warranty length
- Build quality and finish
- Extra features (dimming, emergency, smart control, etc.)
Where thereâs a sensible alternative that still does the job properly, weâll suggest it.
If we think dropping to a cheaper product is a false economy, weâll say so â itâs your reputation on the line,
and weâd rather help you avoid call-backs.
10. âCan you help me put a full list together for this job?â
One of the best questions we get.
Bring us a spec, set of drawings, or even just a rough outline, and we can help you:
- Turn it into a full materials list
- Spot obvious gaps (fixings, glands, clips, accessories)
- Suggest options where the spec allows some flexibility
Youâre still in control of the quote and design, but having a second pair of eyes at the wholesaler can save a lot of time
and reduce the number of âforgot that bitâ trips back to the counter.
Got a question we havenât covered?
If youâve got a question about fittings, compatibility, ratings, replacements or pulling together a job, just ask.
The SED trade counter team deal with these queries all day, every day â and while we canât design the job for you,
weâre always happy to share what we know, check the catalogues and help you find the right kit for the work youâre doing.