Electronics Questions & Answers ← browse Q&As

1) My digital multimeter manual says not to use or store it near strong magnetic fields, but it doesn't specify which equipment generates them. I store my digital multimeter very close to a large CRT TV, and it generates strong magnetic fields that could damage the multimeter if stored long-term near the TV?

https://cdn.leroymerlin.com.br/products/multimetro_digital_hm_1002_hikari_1567477523_575e_600x600.jpg

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQtM9_6sP0H1_EjzI-KcTZIoBfhpDhcfohFqA&s

2) They also mention not storing digital multimeters at high temperatures, but they don't specify what temperature.

If you are concerned about the emf generated by that TV and cannot stored the instruments "far" from it, you could store them inside a metallic enclosure, like an old metallic biscuits/candies box. A metallic drawer for a files cabinet may be appropriate too if there is not too much wide air gaps when the drawer is close.

As for the temperature, military equipment can generally tolerate -40C to 70C, and sensible electronic parts are generally safe, for storage , from 10C to 40C (freezing temperature may harm some electrolytic capacitors). If you have access to the components marking, you can check in their datasheet if they have a note about their storage temperature.

Very sensible equipment for measurements with exceptional precision may need occasional recalibration, generally specified by the maker, in the maintenance instructions (if there is no such instructions, the equipment is probably not of exceptional precision, unless these have been lost by lack of concern by the previous owner, or otherwise). Note that most OpAmp age with time, even when appropriately stored, so the high precision instrument using them still need recalibration from time to time.