Wiring Ceramic heater element or bulb to IEC plug. Help needed!

[joshd963]

Hi all,
My name is Josh & I'm just starting to get into electronics and working on some projects to further develop my skills however have reached and impasse so seeking your assistance. Nice to meet you all
I have some basic electronics skills from messing around with breadboards etc to wiring PA speakers and building a power distro that linked multiple pieces of equipment (low power consumption) into a single IEC outlet. That said my knowledge is still basic especially theory-wise.

I am trying to build a heating device that heats a sheet of plastic to about 160 degrees C in the shortest amount of time possible. I want to use an infrared heat source to directly heat the object. I plan to control the heat lamp with an IEC fused switch like below.


I will use an IR sensor to read the temperature so I know when to turn it off (I know how to do that bit). Later I will build a circuit that automatically switches off when it reaches temperature but that's for another time.

Below I have pictures of the heating methods I have been looking into. The first one is a 1000w ceramic heater with ring connectors, 300c-700c range. The second is a 250W IR reflector lamp bulb.

For the first option I roughly calculated I would need about 4.5 amps to power one, or 9 amps to power two. A few questions if I may on this one:
- Is it safe to wire one or two of these to the above fused IEC connector?
- Am I right in thinking that would need a 5 or 10 amp fuse depending on 1 or 2 heating elements?
- If so how would I wire it? Any ideas how I would wire one or two of these to a IEC plug and is that a safe option?

For the second, I figured I could use four to six of these bulbs in a similar setting with 5/8 amp fuses depending on number of bulbs. Could anybody suggest best way to hook up 4 of these to 1 IEC plug?


Thanks all for reading and appreciate your time taken to respond

Josh

 

[PEG]

Hi bud,is this anything to do with wrapping?

 

[joshd963]

Hi PEG!
Almost, It's for thermoforming plastic sheets maybe 0.75-3mm

 

[Richard Burns]

The fused switch you show is designed for applying power in to a piece of equipment on which it is mounted and not to supply power out, it is dangerous to have the exposed pins live.
You would need to have a socket (outlet) and not a plug (inlet) for your power supply, though I do not think they come fused or switched.
Using a 2 way or 4 way IEC distribution block would be easiest, although you could use splitter cables.
You would need to wire an IEC inlet (such as the switched fused one you show) onto the enclosure in which you mount the ceramic heater being aware of placing it where the heat from the heater will not affect the inlet and ensuring that the heater is earthed if it is required.
For the IR lamps you would wire up the lamp holders for the heaters to an IEC inlet and use IEC extension cables from distribution block to lamp enclosure.
Note that heavy duty IEC parts are rated for 10A and non heavy duty are rated for 5A.

 

[joshd963]

Hi Richard, Thank you for taking the time to reply.


I plan to mount the heating element or bulbs into a frame/housing.

Do you think it will be suitable to mount a 10a or 15a C16 panel mount inlet to the housing? I would then connect that to the mains via a "C15 Outlet - UK 3 pin" cable.


As far as wiring the heating element to the inlet, do I need anything in between the C16 pins and the heating element or simply wire up the heating elements 2 cables to the 2 IEC pins and then wire the IEC ground pin to something metal on the housing?


Look forward to your reply,

Josh

 

[Richard Burns]

Mounting a panel inlet to the housing or frame should be OK, taking due account of not letting it get overheated. You should also ensure that the rear terminals are not easily accessible, if you are using a frame they should be enclosed to prevent inadvertent contact.
They will need a firm fixing to withstand plugging and unplugging the cable.
The connections to the inlet are usually spade (or quick connect) connectors. To fit insulated female spade connectors to the heater cables would require a crimping tool to fix them in place of the ring crimps. The cables as pictured are quite short so you should route them away from the heater as far as possible.
There should be an earth connection on the heater if one is required or a class II symbol if an earth is not needed.

For the heater lamps then I would suggest ceramic lampholders (E27 are easier to find than B22) and then wire from the lampholders with cables that are suitable for high temperature or sleeved with heat resistant sleeving. Then fit spade connectors on the ends for the power inlet.
The 3 pin plug to IEC socket cable should be fine so long as it is rated to 10A and not routed in front of the heaters. A 10 or 13 A fuse should be OK for the plug.
Ensure you are considering safety of yourself, others and the equipment at all times.
Good luck.

 

[joshd963]

Hi Richard,
Is there any way to send you a beer on here?! That was extremely helpful, thank you!!! I'd like to go down the ceramic heating element route as seems best for the task.
Do you know any way I could add a switch (and fuse, if you think it necessary?) into this circuit instead of unplugging the outlet cable every time I want to turn the heat element off? I can't for the life of me find a fused/switched C16 housing like the C14 ones widely available.

I plan to house the connector & wiring in a small aluminium box as far away as possible from the heating element itself (and behind the heating elements reflector also). Am I correct in thinking I can use shielded 12 gauge wire to connect the element to the inlet / switch?

Thanks,
Josh

 

[Richard Burns]

A fuse would not be necessary as the plug has a fuse in it already.
You could install a panel mount rocker switch on the framework diverting the live through the switch before it goes to the elements, you could insert an inline switch into the supplying cable, you could connect the 13A plug into a switched socket outlet, you can even get some plugs which have a switch built into them. Just ensure whatever switch you use is rated to 10A, at least (more of a problem for inline switches).
For cable I would tend to just use high temperature fibre glass sleeving over normal single core cable, but you can use fibreglass insulated cable as is used in ovens and suchlike.

 

[joshd963]

Thanks for your guidance Richard, really helpful and have now finished the designs.
I've ordered all the parts... Will let you know how I get on!
Thanks again.
Josh