Jackal

You need to put a resistor load on the atomizer and run it at 40 watts. I used a halogen bulb. Here is a video of one set up using large resistors: https://www.youtube.com/watch?v=us0rR09PQS4 Here is another using wire loops: https://www.youtube.com/watch?v=d8EHZqiqIbM Cheers! Jackal

Got it working, thanks for your help! Cheers! Jackal

Working on battery curve for Tungsten is tricky. The cold ohms are very low and the live ohms are very high. A workaround is to adjust the punch preheat setting to warm up the filament so the the bulb can fire at the higher resistance setting. Below is a graph for a 50 watt 12 vdc halogen that puts out a maximum of 35 watts on the DNA 250C for various temperature setting, and the resulting live ohms and wattage measured. In the graph, W200, 400 and 600 are the watts at the set temps of 200F, 400F and 600F, with live resistance on the x axis versus output watts on the y axis. Using the graph, you can set the cold ohm resistance to adjust how many watts are delivered for the range of temperature settings. Cheers! Jackal

Thanks, dwcraig1! Will re-run the battery analyzer. Cheers! Jackal

Ran battery analyzer with 1600mah 4S cells fully charged. However, the battery curve the analyzer generated sets 0% at 3.9 volts and 100% at 4.18 volts. Should not 0% be closer to 3.2 volts and not at 3.9 volts? Cheers and all help appreciated! Jackal

They do work great to drain battery for testing, etc, and also make a pretty decent, long lasting heat source for an atty. Below is a table with commercially available halogen bulbs on the left part of table (W1, V1, I1, R) and how they will perform on the DNA 250C on the right part of table (R, W2, V2, I2). Cheers! Jackal

A 50 watt, 22V halogen bulb firing in watt mode. Cheers! Jackal

Yeah, mine was only getting up to 77% because of the unbalanced cell. Ran battery analyzer now that all cells are fully charged and will monitor cell 4 to see if it is misbehaving. Part of my problem is this was my first mod and the solder joints probably suck. After running the battery analyzer, all cells are now balancing. The weird thing is that the battery curve the analyzer generated sets 0% at 3.9 vdc and 100% at 4.18 vdc. Cheers! Jackal

It seems that the lowest cell of the pack determines the percentage charge shown, so if one cell is low, the percentage will be low, and you may have to charge that cell separately to balance the pack . A bad connection on the board could cause a cell to not charge and discharge properly, and this may be the problem with my mod. Cheers! Jackal

Cell 4 at 4.03 volts charging to 4.13 volts to match cells 1-3. Cheers! Jackal

In process of charging unbalanced cell 4 per suggestion of dwcraig1, and seems to be working Cheers! Jackal

retird, thanks for clarifying. The USB recovery charge did not work. Cell 4 is still off by .2 volts. Will try leaving it on USB charging to see if it will eventually charge up or try single cell charging as previously suggested. May also try to reflow solder connections on the board if cell 4 will not charge. Cheers! Jackal

Thanks again! I cleaned the mod with alcohol in case of any discharging due to flux, etc., and will see what happens. As a side note, the USB recovery charging or load balance charging may be working per below picture, as voltages are starting to slowly converge. Cheers! Carlos

Thanks again! Worst case, will let it charge for a few days to see if it will eventually balance, as you suggested. Any idea how power supply mode could help? Cheers! Jackal

Thanks again! Trying the USB recovery charging function and cell 4 is now only .1 VDC off at 23% charge. You guys are awesome, thanks! Jackal

dwcraig1, thanks for the charging tips! Will try that as last resort, as the mod has barely enough room for the components and dread having to pull the battery just to charge the cell that is only off by 0.2 volts. Did that above charging scheme fix the mischarged cell for you long term? Cheers! Jackal

retird, thanks for your quick reply! The DIY mod shown below has the battery and charge balancers connected via connectors to the DNA250C board. Multimeter test confirm the voltages measured by the board are accurate. Not sure if cell 4 is failing but do not see any noticeable swelling. Have not tried (1) power supply mode with battery pack plugged in, and the battery was only purchased on June 20. Have not tried (2) USB Battery Recovery Charging function. Will read about functions (1) and (2) and see if this helps, and post results. At the end of the day, cells 1-3 show 4.2 while cell 4 only shows 3.98 when display shows 77%, so it is not the end of the world. How do functions (1) and (2) help troubleshoot the noted problem? Cheers! Jackal

The DNA250C board display only shows "77%" battery and will not fully charge cell #4 (cells 1-3 fully charged with cell 4 about .2 below others). Escribe shows cell 1-3 having the same charge and discharge rate, while cell 4 is off by about .2 volts when fully charged and off by .2-.5 when at zero charge. Not sure why cell 4 is not fully charging and not allowing the display to show or 100% charge all batteries. Enclosed is a screenshot at 3%. At 77% cell 4 shows about 3.98 volts and will not get to 4.2 like cells 1-3. The battery is a Turnigy 1600mAh 4S 20C Lipo Pack (https://hobbyking.com/en_us/turnigy-1600mah-4s-20c-lipo-pack.html) All help appreciated!

Yes, works with liquid but only a few drops at a time.

Here is the stainless steel pad inside of metal heating tube and installed over a mesh filament for testing.

Here is the halogen material file.

Here is the RDA build deck.

As noted above, got the 50 and 100 watt bulbs to fire in watt mode and also from a DIY halogen material temperature control file. The problem is that tungsten filament has a very low cold ohms and very high hot ohms. The way was able to fire the bulbs is to set the cold ohms higher than actual value (e.g., .33 instead of .19 on 100 watt bulb). Not perfect but works. As far as wicks, pics, etc., attached are some pics of the atty set up. It will be used for dry material and concentrates so no wicks will be used, but rather the bulb will heat a chamber with stainless steel screen or pad on top for convection heating. The pads can also be used for liquids, a few drops at a time. Below is a pic of the halogen bulb in an RDA. Cheers! Jackal

Was able to get the bulbs to fire in watts mode and with a custom DIY halogen materiel file created. The problem with tungsten filament used in halogen bulbs is that tungsten has relatively low cold ohms (0.19-0.22 or so) and high operating ohms (0.9-2.0). Was able to get around this by setting the cold ohms higher that the actual cold ohms and this seems to work in watt and TC modes. As far as wicks, wraps, pics etc., will post some pics of the atty. The bulb will heat a metal container with a screen or pad on top for heating by convection dry, liquid and concentrate materials. Cheers! Jackal

Built a 250C mod box with 1600 mah 4S LIPO pack. Trying to get a DIY 50-100 watt halogen bulb atomizer to stop throwing "temp control" error in watt mode (or any mode). The atomizer with either the 100 or the 50 watt bulb runs fine on a 24VDC supply, and below is the measured data for the 100 and 50 watt bulbs. All help appreciated trying to get this atomizer working in the mod. Cheers! Jackal