Why Do I Need a Blocking Diode on My Solar Panel?

Why Do I Need a Blocking Diode on My Solar Panel?

Blocking diodes in photovoltaic systems serve two functions. They can prevent batteries from draining at night, and can isolate damaged or under-performing solar cells. The latter can be solved with either a blocking or a bypassing diode.

Function
A diode is a semiconductor device, a one-way valve for electricity. Diodes are rated in the maximum current they can pass through while on and the maximum voltage they can block when off. When the correct conditions are met, the diode will stop current from flowing.

Shaded Panels
Solar panels contain several solar cells wired together in series. If part of the panel is shaded, all of the cells become less efficient.

Bypass Diodes
A blocking diode in the panel "averages out" any shaded cells. The diode allows the loss of voltage from a shaded cell to be shared among the others, so that the panel functions more normally.

Battery Drain
At night, dusk and dawn, the battery outputs a higher voltage than the solar cells do. Without a blocking diode, the battery will send power to the panels instead of the other way round. Over time, this can drain the batteries.

Blocking Diodes
When the battery voltage is higher than that of the solar panel, a blocking diode shuts off flow. During the day, the blocking diode can also prevent drain from the battery caused by damaged cells. In a function similar to bypass diodes, the bad cells are isolated from the others.

How to Change a Car Circuit Breaker

How to Change a Car Circuit Breaker

Many of the circuits in today's car and trucks are protected by a circuit breaker. The circuit breaker comes in three different types--plug-in, inline and tab-mounted. While the failure of a circuit breaker is rare, replacement is sometimes necessary, and is a task easily handled by the car owner.

Things You'll Need

Replacement circuit breaker

Instructions

Check your owner's manual for the location of the circuit breaker which protects the problem circuit. Modern vehicles have as many as three electrical distribution panels making finding a failed circuit breaker very difficult without the manual.

Determine the type of breaker. A plug-in breaker will be inside a power distribution panel, while a tab-mounted breaker will be attached to the vehicle with a rivet or screw, and an inline breaker will be installed along the wire.

Grasp a plug-in breaker firmly and gently pull it directly away from the panel to remove it. Install the replacement breaker by pushing it straight into its holder. Don't be concerned about polarity, as a circuit breaker can be installed in either direction.

Remove the two small nuts from a tab-mounted or inline breaker to detach the wiring from the studs. It is a good idea to disconnect the negative cable from the vehicle battery first.

Remove the screw holding the circuit breaker to the vehicle. Some tab-mounted breakers are held in a plastic bracket. To remove, pull the breaker out of the retainer until the tab is released. Reverse this step to install the new breaker.

Know that an in-line breaker is held only by the wiring to which it is attached. Removing the wiring from the studs releases the breaker, so you simply have to install the wires to a new breaker to replace this type of breaker.

How to Replace a Car Fuse Relay Box

How to Replace a Car Fuse Relay Box

An automotive fuse box, sometimes called the circuit panel box or fuse block, has the unique function of protecting every electrical circuit in the vehicle. These circuits include all the engine, transmission, suspension and brake component sensors, the main computer and all the many accessories and components in the electrical system. Blown relays and fuses can be a relatively easy fix, but when the relays and fuses check out and the components test good, the main fuse panel box can be the culprit. The automotive DIY repair person can change out his fuse box by following some simple steps and using a few basic tools.

Things You'll Need
Owner's repair manual
Socket set (1/4-inch)
Ratchet wrench
Socket extension (1/4-inch)
Rags
Masking tape
Felt pen
Screwdrivers


Instructions
Place the car or truck in park or neutral, according to your transmission type. Set the emergency brake. Use a socket and wrench to disconnect the negative battery cable from its post. Disconnect the positive battery cable, for added insurance. Wrap both cable ends with rags to keep them from metal contact. Locate your fuse box by referring to your owner's repair manual. Look for it on the driver's side inside the lower kick panel, in the engine compartment or in the glove box.

Pull the fuse box cover lid off and set it upside down, so you can reference the schematic fuse diagram. Look for a large red cable, or cables attached to the fuse box, which will be the main battery supply cables. If they bolt to the top of the fuse box, use a small socket and ratchet to unscrew the nuts. Place masking tape around the wire (or wires) and use a felt pen to mark them, according to their descriptors in the diagram. Wait if your main battery wires connect underneath.

Look for the fuse box screws holding it to the dashboard, firewall or glove box frame. There could anywhere from two to six or more small screws. Remove the screws with a flat-head screw driver, or very small socket. Keep the screws in order. Gently turn the box over and look at the wire connectors. If your main battery wires connect in this location, unscrew them with a small socket, then tape and mark them with a felt pen.

Look for any small wires that have nut and eyelet connections on the underside of the fuse box that require removal. Remove them one at a time with a small socket. Tape and mark each one for placement identification. The rest of the connectors will snap into the sides of the fuse box. Use a small screwdriver to lift the plastic tabs on each connector and pull it free. Tape and mark each connector and its location, then push them gently out of the way.

Remove the old fuse box. Set your new fuse box next to the old one and compare the fuse and relay arrangement. It must be an exact duplicate. If your new or replacement box does not have relays and fuses in it, lift each fuse out of the old box and place it in its corresponding slot location in the new box. Replace them one at a time, and check the amperage rating on the fuse or relay with the schematic numbers on the fuse box or from the owner's manual.

Place the new fuse box next to its mount location. Hook up the small eyelet wires you removed, reading your felt pen marks. Screw the wires back down with a small socket. If the main battery eyelet wires connect from the underside, attach them now and screw down the eyelet nuts with a small socket. Place the fuse box in its mounting location and twist the mounting screws in by hand. Tighten the mounting screws with a small socket or screwdriver.

Reconnect the positive battery cable with a socket. Replace the negative battery cable and tighten it with a socket. Cycle the ignition key on and off several times. Start the vehicle and check the function of all the accessories. If an accessory fails to operate turn the engine off, disconnect the negative battery cable with socket and check the fuse to that accessory.

How to Fix a Faulty Car Fuse

How to Fix a Faulty Car Fuse

Fuses protect your car from electrical short circuits and power overloads that can damage equipment or start a fire. Often, a fuse will blow due to a momentary overload, and replacing the bad fuse as directed below will fix the problem (a car's horn or interior lights may cease to work, for example). If a fuse blows repeatedly, it indicates an electrical problem that will require a trip to your mechanic.

Instructions

Things You'll Need

• Fuse Puller Or Needlenose Pliers
• New Fuse (same Amperage And Type As The One You Are Replacing)

1. • 1
     

     Find the fuse box (see A). It is usually located under the dashboard to the left of the steering wheel, at about knee level. Many cars have additional fuse boxes in the engine compartment. Check your owner's manual or call the dealer for the exact location(s).
   • 2
     

     Open the fuse box cover and locate the blown fuse. There are two ways to find the bad fuse: Look for a fuse with a melted center strip (see B, which shows two types of broken fuses). Or, if you know which device isn't working--for example, the radio--look for the fuse that handles that device. The fuse panel may have labels for each device, or the information may be in your owner's manual.
   • 3
     Remove the bad fuse with a fuse puller (a small pair of plastic tweezers that should come with the fuse box). Or use a pair of needle-nose pliers.
   • 4
     Check the number on the bottom or side of the bad fuse. This indicates the amperage.
   • 5
     Buy a new fuse with the same amperage and push it into the slot in the fuse box with your fingers.

How to Remove Car Fuses

How to Remove Car Fuses

Advancements in motor vehicle safety have rocketed, and the fuse has been a consistent feature through the decades. Electrical systems and accessories are protected by the fuse's design to fail in the event of an electrical short or overload. Other times, the fuse just gives out and you may find yourself without working wipers, lights, horn or heat. Armed with a little knowledge, a tool and a spare fuse, you can be back to full power in minutes.

Things You'll Need

Owner's manual

Safety glasses

Flashlight

Small pliers

Fuse puller

Fuses

Instructions

Consult your owner's manual. It will inform you of the location of the fuse box, the type of fuse, its amperage and the electrical components associated to it. On newer models, the fuses will be small, plastic two-pronged tabs plugged into a slot. They will be red, green, blue or yellow depending on the amperage. Amps are marked on the panel and corresponding fuses, and generally range from 5 to 35 amps in increments of 5. Older vehicles have small, glass, tubular fuses 1/2 to 1 inch long with stainless steel caps on each end. The amps are stamped on the caps, and the different amp fuses are different in length.

Locate the fuse panel. On most vehicles, it will be under the dashboard on the driver's side, and you'll need a flashlight. Other locations include the lower half or side of the driver's dash panel, inside the glove box, and under the hood near one of the fenders or firewall. The fuse panel cover often has the word "fuses" written on it. The panel size ranges from the size of an iPod to a sandwich (under dash) and slightly larger under the hood. Older models don't have panel covers and are commonly to the left of the brake and parking brake pedals.

Pull out or pop off the fuse panel cover. If you don't have your owner's manual handy, there is usually a chart on the inside of the cover with fuse locations and details. There are also amps and associated components stamped on the panel beside each fuse, matched with labels or numbers.

Identify which fuse matches your electrical problem.

Remove the blown fuse. Cars with plastic fuses often have a special tool in the fuse panel or cover. The fuse puller resembles small plastic tweezers and has special teeth at the end that grab the lip on the fuse. The older glass fuse models did not come equipped, and a puller can be purchased at an automotive supply store. Small regular and needle-nose pliers can be used for both fuses, and they can be pulled by hand with some difficulty because of the awkward size and location. Glass fuses will break with little force, or if the fuse is rusted at the ends. Use protective eye wear. A small screwdriver can also be used to pry one end of the fuse out, and you can wiggle it out with your fingers.

Inspect the fuses. The plastic fuses are transparent, and you'll see the U-shaped metal link inside that connects the two prongs. If it is blown, the link will be broken. The glass fuses have a thin filament that breaks when blown.

Replace the blown fuse with the same length and rating (glass) or same color and rating (plastic). Some newer models are equipped with spares, otherwise you can purchase them at your local automotive and department stores. Grab the plastic fuse with your fingers, holder or pliers and push it into the slot. The glass fuse snaps in one end at a time. Be careful not to push so hard that you break the glass and cut yourself.

Check the electrical component in question. If the fuse blows again, there is a fault in the wiring or component.

What Is the SBA Fuse for in a 2003 Chevy Silverado?

What Is the SBA Fuse for in a 2003 Chevy Silverado?

The 2003 Chevrolet Silverado is a member of the first generation of Chevy’s full-size pick-up line that replaced the C and K models. It is also the counterpart to GMC’s Sierra. The two truck lines closely resemble each other and share many parts, which lowered design, inventory, and acquisition costs. This generation lasted eight years, introducing many model, trim and engine options. These options include the 1500, 2500, 3500, Heavy Duty, Super Sport and Denali with multiple gasoline and diesel powerplants available.

SBA Fuse
The 15-amp SBA fuse in your underhood fuse box is for the Supplemental Brake Assist system. This indicates that your truck has vacuum assisted power braking technology. The Supplement Brake Assist system supplies additional vacuum power to the vacuum assisted power brakes when the engine’s vacuum is diminished. This is accomplished by starting a small motor which generates the additional vacuum power. When the supplemental system is activated, you should feel a slight vibration in the brake pedal. It is normal for the system to activate under certain driving conditions. However, if you feel the supplemental system activate every time you apply the brakes, this may indicate a vacuum leak somewhere in the engine vacuum system.