Power Supply Plan 24 Volts 300Watt heatpad

24 Volt to 12 Volt Automotive buck convertor inside

I have now replaced this, it gets too hot form my liking with a 12 Volt PSU

Chaining it to a 12 Volt PSU, it gets too hot for my liking, even with fan, extra heat sinks. Temp testing:-

https://www.youtube.com/watch?v=V7qvEhXDFXA

STEP DOWN UNIT: NOT RECOMMENDED

This step down unit produces a lot of heat even with the fan and heat sinks added

RAMPS 1.4 etc in a shoebox from 24 Volts so I added a fan and some heat sinks

24V to 12V DC-DC 30A Car Power Supply Inverter Converter Conversion Device
Convert your DC 24 volts to DC 12 volts with this compact power supply converter

My power supply inputs 23.81 Volts and this unit outputs 11.62 Volts.

HEAT!!! I added a small fan, 25mm inside connected direct to the 12 Volt output pads inside. I have also put it, the RAMPS and SSR, into a box with a 70mm computer fan. I, not fully tested found the case, outside, of the unit, (this is used as a heat sink), getting quite hot, this seemed to be more, (not fully tested), when I powered a small 12 Volt light strip from it, Low Amps.

So do not use it without external cooling.?

I now power the LED strip and fans from the red 12 Volt output, lower Amps output, of this unit and the RAMPS 12 Volts from the Yellow higher Amps output.

The RAMPS caused some flicker to an LED strip, passing some voltage PWM form hot end to the RAMPS input.

The circuit is now like this:-

https://hackaday.io/project/8680/gallery#d2769ed6055a46e72534c2ed2e978abb

LED lighting flicker.

I have some strip LED, 12 Volts, fitted to the 3D Printer to light it up.

Originally I powered these by having them plugged into the RAMPS 1.4 power input which gets it's power from the 24 Volt to 12 Volt buck converter using the Yellow 30 Amp wires.

This caused the LED strip lights to flicker when the hot end temperature reached it's set temperature, I believe this uses PWM once it gets to the requested temperature. It appears as if some of this PWM voltage/signal is passed onto the power input ports on the RAMPS 1.4 casing LED strip lights connected in here to flicker. The LED strip lights would flicker at the same rate and time as the Hot End LED would on the RAMPS 1.4 board.

This was annoying.

I changed the LED strips from using the Yellow wire out and use the Red wire output with the supply using the same 24 Volts input to the Red and the Yellow, on the input side.

This resolved the flicker issue and the LED strip lights and now stable.

So for the 24 Volts to 12 Volt buck converter:-

Input 24 Volts positive to the input side going to both Red input and Yellow input

The 12 Volts outputs Yellow, (high up to 30 Amps), wire going into the RAMPS 1.4, both to the 5 Amp and 11 Amp input on the RAMPS 1.4 board.

The 12 Volts outputs Red, lower Amps), to power the LED strip, and other 12 volt parts.

Protomaker 3D Printer Heat bed SSR test success. RAMPS 1.4 via 24 Volts using the above 24 Volt to 12 Volts method

3D Printer 24V Heat bed SSR test success

Using RAMPs 1.4, with a 12864 LCD display, control a 24 Volt 300 Watt heat pad.

The 24 Volt 300 Watt heat pad is controlled on and off via the Solid State Relay, SSR.

The Solid State Relay is controlled via the RAMPS 1.4 which is powered via a 24 Volt to 12 Volt car voltage step down device. A 24 Volt 500 Watt Power supply unit powers the 24 Volt 300 Watt heat pad via the Solid State Relay which is controlled via the RAMPS at 12 Volts.

So the RAMPS 1.4 is powered at 12 Volts via 12 Volts from the car voltage step down device which gets its 24 Volts input from the same 24 Volt 500 Watt Power supply as the one that also powers the 24 Volts 300 Watt heat pad.

Video:-

http://www.dailymotion.com/video/x3lqf51_protomaker-3d-printer-heat-bed-ssr-test-success_tech