I worked on a SMT QRP RF Power Amp Circuit until very late last night, near the end, my cordless Soldering Iron was just keeping up, if I let it set in it's charger every few minutes. It was very late (early AM) when I quit. To avoid a low battery for the next day (today), the last thing that I did was make sure that the Soldering Iron was on Charge mode.
This morning, I grabbed the Soldering Iron - fully charge and started work - on the very first try the work lamp blew out, with a bright flash. Too much charge or an old lamp on my new Soldering Iron. Dang!
The replacement lamp is about $5.00 and it would take several days to arrive.
The lamp probably draws about 250ma, which is a waste of my cordless Soldering Iron Charge.
I think, I am going to look into wiring up an LED - I normally do not need the light to see the work. For me, the light brightness is an indicator of heating status.
So, now I have yet another project!