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Incoherent · 09-09-2005, 12:31 AM

I guarantee that you will be able to use these heaters with DC Jaydee. Problem is is that the resistances of these are rather high so you need a high voltage DC power supply to get the power output you want.
Using several of them with AC in different configurations would give you some control. eg 3 50W heaters gives 50W, 100W, 150W and then 1 + (2 in series) gives 75W, 3 in series gives 16.7W. This is a bit of a stupid way to do it though with complicated switching so you don't short circuit your power supply by accident. A Variac (a variable transformer) would be ideal for this but I suspect they aren't cheap and it is difficult to measure power accurately.
Low resistance heaters using DC are far easier to control, thats why I use these, but I would actually suggest something like this with a STRONG caveat that you have some kind of over temperature protection and design the heat die so that there is a minimum of material between the heater and the tested heat exchanger to keep the temperature of the load at a minimum (they have different ratings at different temperatures.)

09-09-2005, 12:31 AM	#18
Incoherent Cooling Savant Join Date: Sep 2003 Location: Vallentuna, Sweden Posts: 410	I guarantee that you will be able to use these heaters with DC Jaydee. Problem is is that the resistances of these are rather high so you need a high voltage DC power supply to get the power output you want. Using several of them with AC in different configurations would give you some control. eg 3 50W heaters gives 50W, 100W, 150W and then 1 + (2 in series) gives 75W, 3 in series gives 16.7W. This is a bit of a stupid way to do it though with complicated switching so you don't short circuit your power supply by accident. A Variac (a variable transformer) would be ideal for this but I suspect they aren't cheap and it is difficult to measure power accurately. Low resistance heaters using DC are far easier to control, thats why I use these, but I would actually suggest something like this with a STRONG caveat that you have some kind of over temperature protection and design the heat die so that there is a minimum of material between the heater and the tested heat exchanger to keep the temperature of the load at a minimum (they have different ratings at different temperatures.) Last edited by Incoherent; 09-09-2005 at 12:56 AM.