The adjustable internal resistance battery is a DC power supply designed for physics experiment teaching. It is a single lead battery with a certain capacity, the electromotive force is relatively stable, and its internal resistance is relatively large and continuously adjustable. Since the adjustable internal resistance battery is not sealed, great care must be taken when using it to prevent acid splashing. Improper use and maintenance will affect the service life. Charging the adjustable internal resistance battery: the prepared dilute sulfuric acid is charged into the adjustable internal resistance battery, and the acid solution just immerses the polar plate. The constant current method can be used to charge the constant voltage part of the student power supply. A sliding rheostat should be connected to the charging circuit to adjust the size of the charging current, and an ammeter to monitor the charging current. The battery must be charged in time after use, and the charging time is about 30. Maintenance of the adjustable internal resistance battery plate: Since the adjustable internal resistance battery is only used for more than one month a year, most of the time it is left unused. Pay special attention to the preservation of the battery plate. . (1) The polar plate can be stored in the electrolyte of the battery, and must be recharged regularly. Because the adjustable internal resistance battery 1 is not sealed, it is easy to evaporate, causing changes in acid density or other reasons. The polar plate of the battery is also very easy. Damaged, it is not easy to keep for a long time. (2) Dry storage method: The electrode plate can be dried and stored. When the electrode plate is dry and stored, it needs to be treated as follows: charge first, rinse the positive and negative plates in clean water after charging, the positive plate can be stored in clean plastic paper after it is dried; the negative plate is dried in a rosin alcohol solution Medium dipping. After the alcohol volatilizes, store it in clean plastic paper. When the battery is reused, insert the electrode plate directly into the battery, inject the electro-hydraulic, and perform a normal charge. Since alcohol will adversely affect the lead dioxide insulation ladder, the anode plate should avoid contact with the rosin alcohol solution when handling the electrode plate. Probe maintenance: When the probe is inserted into the battery to complete the experiment, take it out in time and rinse it with clean water in a beaker to prevent polarization of the probe. The probe generates polarized electromotive force, which seriously affects the experiment. If the probe is polarized, it can be removed by the following methods: (1) The two probes are short-circuited, washed with water to remove sulfuric acid, dried with a dry towel, and then sanded off the oxide layer on the surface to be used, but this method takes a long time and cannot completely remove the polarized electromotive force. (2) The two probes can be connected to the alternating current to energize, this method can completely remove the polarized electromotive force. If the probe will not be used for a long time, rinse the acid solution with clean water, dry it and wrap it with plastic paper for storage.
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(Details
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