Re: Packard Heaters
Posted by HH56 On 2017/4/28 16:52:21
For those looking for real Packard deluxe heater switches -- which may or may not be easy to find -- here is a method of using a modern AC switch to do an automatic reversal of the motor using relays. It will permit operation of a heater until a real switch can be found. It provides one fast defrost speed and two heater speeds. Using the square switch shown it will fit inside the Packard decorative plastic housing which was used under the dash in some years.
Briefly, operation is when switch is turned to first position, two relays energize. First relay provides full voltage to motor and second causes the motor to turn in the defrost direction. When the second switch position is made relays drop out. First relay selects a different voltage path for the motor and second changes direction for heater function. Motor voltage goes thru the resistor for low speed. The final position just bypasses the resistor to provide full voltage to motor again. Motor reversal is done by changing the relationship between the armature and field. If after building the circuit, motor direction is not proper for the heat or defrost function it can be fixed by swapping the green and red wires fed from the second relay.
A less automatic basic manual method but with infinitely variable speed is shown on the second schematic. That uses a universal 6v heater switch for the speed and a manually operated toggle switch to reverse the motor. Same wire swap would be needed to change direction. 6v switches seem to be somewhat limited in style but a 12v will have too much resistance so will not work well.
If anyone tries to build the circuit one thing to be aware of is what appears to be a difference in how the motors may be wired between deluxe heaters. I have a 40 model and mine, Joe Santana's and one other posters all seem to work the same way. When I tried hooking up my 40 heater to the 41 Clipper switch it did not function with the colors wired per Packard. Examining the switch to find how it did the reversing would lead me to believe the wiring is different on that later heater motor. I have indicated what I think to be correct for the motor but without having documentation or one to examine that is pure speculation. I can't say which pair are field or armature -- only that the Clipper switch reverses the direction using the brown and red wires by changing their connections to the yellow and to power.
Attach file:
(141.35 KB)
Briefly, operation is when switch is turned to first position, two relays energize. First relay provides full voltage to motor and second causes the motor to turn in the defrost direction. When the second switch position is made relays drop out. First relay selects a different voltage path for the motor and second changes direction for heater function. Motor voltage goes thru the resistor for low speed. The final position just bypasses the resistor to provide full voltage to motor again. Motor reversal is done by changing the relationship between the armature and field. If after building the circuit, motor direction is not proper for the heat or defrost function it can be fixed by swapping the green and red wires fed from the second relay.
A less automatic basic manual method but with infinitely variable speed is shown on the second schematic. That uses a universal 6v heater switch for the speed and a manually operated toggle switch to reverse the motor. Same wire swap would be needed to change direction. 6v switches seem to be somewhat limited in style but a 12v will have too much resistance so will not work well.
If anyone tries to build the circuit one thing to be aware of is what appears to be a difference in how the motors may be wired between deluxe heaters. I have a 40 model and mine, Joe Santana's and one other posters all seem to work the same way. When I tried hooking up my 40 heater to the 41 Clipper switch it did not function with the colors wired per Packard. Examining the switch to find how it did the reversing would lead me to believe the wiring is different on that later heater motor. I have indicated what I think to be correct for the motor but without having documentation or one to examine that is pure speculation. I can't say which pair are field or armature -- only that the Clipper switch reverses the direction using the brown and red wires by changing their connections to the yellow and to power.
Attach file:
(141.35 KB)
This Post was from: https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=190885