Realdo, the power panel connect 12 volts to the plug for about 10 milliseconds then nothing for the next 90 milliseconds for an average of about 1.2 volts. The current measurement can not be made with a conventional ammeter, only by a true averaging meter (a very rare animal). The peak current pulse is quite high (roughly 10 times the average current). That is why you can blow out a glow plug using the power panel when you turn the gain (pulse width adjustment) to high. If you have a friend with a scope or access to an electonics lab, it is interesting to look at the wave form accross the plug.