PTC Heater Housing

prusaprinters

This is a remix from the Photonsters PTC Heater Unit made by X3msnake located here https://www.thingiverse.com/thing:3442165This version uses a relay to control the fan and PTC heater instead of a thermostat so it can be controlled by Octoprint using the Enclosure plugin.Fan guard is secured with M3x25mm Socket Head screws, relay is secured with M3x4mm Socket Head screws.Relay used is the HiLetgo 2pcs 5v one channel module located here https://www.amazon.com/dp/B00LW15A4WThe relay can be triggered with 3.3v for use on a Raspberry Pi.  Wire the heater/fan in NO mode with trigger set to high, wired to any GPIO from 9 to 27 (default low), so it's off unless you trigger it on.  Relay direction inside the housing is the NO/COM/NC side (left side if looking into the housing) opposite to the power connector, so it won't hit the relay and has a bit more room for the larger wires.Printed grommet for control wire is 22AWG 3-Core wire with a jacket OD of 4.7mm.  Used the following wire https://www.amazon.com/dp/B07TJFZ3FPUse a properly rated power connector (10A capable or greater) to avoid extra heat buildup such as the following https://www.amazon.com/dp/B07C46XMPTWire the 12v fan and PTC heater red wires into the NO terminal on the relay, then wire from the COM terminal to the positive terminal of the 10A power connector.  Check your power supply for what post is positive and negative, not all power supplies are the same.  Wire the black wire from the fan and heater directly to the negative terminal on the power connector.  If you want the fan on 100% of the time, wire the red wire from the fan directly to the power connector instead of through the relay.When fully assembled there is very little space to work with, protect exposed wires and terminals with heat shrink to prevent shorting.When assembling, you NEED the plastic spacer from the original PTC heater housing.  It goes between the heater and the fan.  Follow most of the assembly instructions from the original post linked above.  Make sure you get a properly sized power supply!Printed in PETG with supports and 25% infill.