I'm trying to match a Petzl Zoom bulb so I can buy a few, but the only identification marks on it are the Petzl name and 4.5V.
Any idea what ampage the bulb that comes with a zoom is? It's the tubular and nippled bulb not a spherical bulb.
I bought a few from Caving Suppies in Buxton to test them out but none of them seem as bright. I bought 4.0V 0.5A, 0.85A and a 1A bulb to see if the extra rating would ioncrease the brightness significantly enough to do with the loss of duration but I can't see a huge power difference. Does the 4.0V as opposed to 4.5V rating make a difference?
I'm assuming from struggling through the principles of Ohms law that it might as I imagine the resistance of the different bulbs is similar? Or am I barking up the wrong tree.
Many thanks,
Ian B.
Any idea what ampage the bulb that comes with a zoom is? It's the tubular and nippled bulb not a spherical bulb.
I bought a few from Caving Suppies in Buxton to test them out but none of them seem as bright. I bought 4.0V 0.5A, 0.85A and a 1A bulb to see if the extra rating would ioncrease the brightness significantly enough to do with the loss of duration but I can't see a huge power difference. Does the 4.0V as opposed to 4.5V rating make a difference?
I'm assuming from struggling through the principles of Ohms law that it might as I imagine the resistance of the different bulbs is similar? Or am I barking up the wrong tree.
Many thanks,
Ian B.