novicefedora
- Jun 25, 2020
- 25
- Joined
- Jun 25, 2020
- Messages
- 25
Is there any risk of shock from attaching or detaching wires to a 9V battery? When I'm cutting wires soldered to the battery and PCB or attaching or soldering one wire at a time?
No, unless the battery is connected to a large inductive load. That will generate a high back-emf when its current is interrupted; high enough to give a nasty jolt but unlikely enough to kill you (unless you have a pacemaker or heart-condition).
Yes.Can this copper coil act as an large inductive load.
A bug zapper includes an inductor for stepping the voltage from the battery up to a very high voltage which may well be rectified and held on a capacitor. That could be enough to give you a nasty schock. The same arrangement is used in a camera's electronic flash. The camera manual would normally contain a warning message about the danger.
Yes.
You switch off the device and make sure that any capacitor in the device has time to discharge. This may take a second or so if the circuit has been designed properly to include a discharge path, or may take a lot longer in a cheapo circuit with no such intended path.Then how would I disconnect, reconnect and solder wires with an inductor?
You switch off the device and make sure that any capacitor in the device has time to discharge. This may take a second or so if the circuit has been designed properly to include a discharge path, or may take a lot longer in a cheapo circuit with no such intended path.
Depends how the circuit has been designed.Will turning it off and pressing the zap button discharge the capacitor?
Only if you have a meter rated to handle the very high voltage.Can I check this with line tester or multimeter?
A bug zapper includes an inductor for stepping the voltage from the battery up to a very high voltage which may well be rectified and held on a capacitor. That could be enough to give you a nasty schock. The same arrangement is used in a camera's electronic flash. The camera manual would normally contain a warning message about the danger.
Yes.
Both.Do you mean standalone camera flash attached to DSLRs or the ones found in disposable cameras?
The flash duration in a camera flash unit (other than a disposable camera) is usually adjustable by the microcontroller in the camera or standalone flash.Will a standalone camera flash give me more control over the duration of the EMP pulse, like making it last for only 1ms,
Where are other silly EMP threads?Not another silly EMP thread!
In our "twilight zone" section. Should you so wish I can easily move this thread over there.
Definitely not as it is not possible to reply in that section.Will this thread get more replies there?
An offer.Is that a threat?
Simply avoid terms that sound like woo woo science.EMP is secondary.
There definitely is if there are high voltage parts that are charged,I think the main point of this thread is to find out if there is any risk of electric shock when detaching, attaching wires, which are connected to batteries, PCBs with high voltage converters, capacitors.
Definitely not as it is not possible to reply in that section.
An offer.
Simply avoid terms that sound like woo woo science.
There definitely is if there are high voltage parts that are charged,
The reasons for this can be manifold:
- high battery voltage (yes, batteries of electric vehicles can have more than 100 V)
- generated high voltages (as in electronic flashes, vacuum tube operated devices etc.)
The general procedure is to deactivate the device, disconnect the battery (assuming it is of the standard low voltage type this is an easy task) and wait for any charges to be discharged. In a good design so called bleeding resistors will discharge high voltage components within a few seconds or minutes. In a less well designed circuit lacking bleeder resistors the discharge can take very long. It may be aided by manually connecting a bleeder resistor across suspect components (e.g. capacitors).
Without further knowledge of the circuit in question no more detailed advice can be given.
So your zapper is fed with AC voltage which probably gets rectified to drive an oscillator. The oscillation gets stepped up by the transformer then rectified and stored on the 2000V cap. If there is a bleed resistor across that cap, it's not evident from the pic. Methinks the cap would hold a possibly lethal charge for a considerable time.