INPUT ARTICLE: Article: The manufacturer's part number should be listed on the case of the relay. Look up the applicable data sheet and determine the voltage and current requirements of the control coil. This also may be printed on the case of larger relays. A diode around the pole is often used to protect the logic circuitry from damage due to noise spikes. The diode will be shown on drawings as a triangle with a bar across one corner of the triangle. The bar will be connected to the input, or positive connection, of the control coil. This will also be available from the manufacturer's data sheet, or may be printed on the case of larger relays. Relays may have one or more poles, indicated in drawings by a single line switch connected to a pin of the relay. Each pole may have a normally open (NO) and or normally closed (NC) contact. The drawings will indicate these contacts as connections with a pin on the relay. The relay drawings will show each pole as either touching the pin, indicating a NC contact, or not touching the pin, indicating a NO contact. Use a digital multimeter (DMM) to test the resistance between each pole of the relay and the corresponding NC and NO contacts for that pole. All NC contacts should read 0 ohms to the corresponding pole. All NO contacts should read infinite resistance to the corresponding pole. Use an independent voltage source appropriate for the rating of the relay coil. If the relay coil is diode protected, make sure that the independent voltage source is connected with the proper polarity. Listen for a click when the relay is energized. Use a digital multimeter (DMM) to test the resistance between each pole of the relay and the corresponding NC and NO contacts for that pole. All NC contacts should read infinite resistance to the corresponding pole. All NO contacts should read 0 ohms to the corresponding pole.

SUMMARY: Determine the coil requirements of the relay. Find out if the control coil is diode protected. Assess the contact configuration of the relay. Test the de-energized condition of the relay contacts. Energize the relay. Check the energized condition of the relay contacts.

INPUT ARTICLE: Article: Crystal cat litter is made of silica gel. This material is extremely absorptive and will do an excellent job of pulling residual moisture out of a water-damaged phone. You can purchase crystal cat litter at any large grocery store or pet-supply shop. Do not use any other type of cat litter. Clay-based or powdery litters may stick to your phone and turn it into a wet, clay-covered mess. Instant oatmeal is more absorptive than regular rolled oats and more much absorptive than steel-cut oats. If you already have instant oatmeal in your home cabinet, it may be the most effective substance you can use to dry your phone. Be aware that if you use oatmeal to dry your phone components, you may end up with a phone covered in small, gooey bits of oatmeal dust. You can purchase unflavored instant oatmeal at your local grocery store. Synthetic desiccant packets are those 34in (1.9cm) packets that come in various commercial items including shoe boxes, dried foods (like beef jerky or spices), and electronic devices. The packets are typically filled with highly absorptive silica beads which will pull moisture out of your phone. You do not need to tear open the packets. Simply pile them up on top of your phone and let them pull the moisture out. This option will only work if you've been saving up silica gel packets in advance for several months. However, this isn't a bad idea: many people own smartphones, and the chances of dropping your smartphone in water at some point are high. Or, if you haven't been saving up silica gel packets, you can order them in bulk through major online retailers. Couscous is a type of crushed and dried wheat grain. The small, dry grains will work similarly to silica beads or instant oatmeal and pull any residual moisture out of your phone components. You can purchase couscous pearls at any grocery store or supermarket. The pearls shouldn't get any couscous dust on your phone's components, making this a cleaner option than instant oats. Be sure to purchase an unflavored and unseasoned variety.

SUMMARY:
Try some crystal-based cat litter. Give instant oatmeal a try. Find some synthetic desiccant packets you could use. Use couscous pearls to dry your phone.