 |
|
Do I need a diode for my wind turbine?
- If the turbine has brushes then yes, you need a diode.
- If it is d/c motor, then yes you need a diode.
- If it is single phase A/C you need a single phase bridge rectifier.
- If it is 3 phase A/C then you need a 3 phase bridge rectifier (like a car alternator), if it is not already included.
- Check with your turbine supplier for more info.
Click here for a 3 phase wind turbine hookup/wiring diagram
Do I need a diode for use with my solar panel?
PV panels require a diode to prevent current flow back into the battery when there is little or no light. This is called a blocking diode. We sell 3A and 8A diodes for this purpose. You might also want to install a bypass diode to prevent a shaded panel from drawing down other panels. These same diodes can be used. Place diodes in the PV J-Box. If you are using a solid state controller, you may not need a blocking diode. Our C150-SMA does not require a blocking diode.
Does a diode come with your charge controller?
No, diodes are specific to your application and the size and placement of the diodes depends on your site and energy sources in use. Different turbines require different types of diodes/rectifiers (and some do not require any). PV panels require yet a different type of diode. Please see the other Q&As here for more information on diodes.
Where do I put the diode for my solar panels?
For solar panels, we recommend you put one blocking diode on each PV panel, inside the J-BOX. The diode needs to have a voltage and amperage rating above that of the panel.
Ex: If you have two 175 watt panels each at 42 volts. You will need (two) 8 Amp, 45 volt diodes. (175 watts / 42 volts) = 4.16 amps.
+ (plus) side of the diode goes to the PV panels + (plus) terminal
Where do I put the diode or rectifier for my wind turbine?
Blocking diodes and rectifiers go between your turbine and the battery bank. If you have a disconnect switch between your turbine and battery bank, then you can put your diode/rectifier on either side of this switch. Keep in mind if you have a 3 phase turbine, you need a 3 phase switch if you place the rectifier on the battery side of the switch.
Which side is the plus side of a diode?
Smaller diodes have a silver, gray, black or white band on the cathode (negative side.) The positive side is generally unmarked.
Larger stud diodes will show the arrow and line -->|--
For the symbol above: The negative side is on the right. Think of it as the current can go with the arrow, but not the other way since it hits a wall.
--> Yes,
--| No
Look closely at the the diode on the left and you will see the symbol
on the right side. This shows the current goes though the diode from the
top to the bottom. For this particular stud diode, the top portion is
the anode (positive) and the bottom is the cathode (1/4" threaded
portion.) Stud diodes are also available with with the cathode on top
(Although we do not currently sell them.)
What direction does my diode go?
The positive (anode) side of the diode always goes towards your energy source, this is where your energy is coming from.
So for a solar PV panel, wind turbine, hydro etc., the anode goes on (or towards) the energy sources positive lead. No diode is required on the negative lead.
What size diode do I need?
Your diode needs to be somewhat larger than the current that is will be handling. For solar panels, we sell the 3A and 8A diodes for this purpose. If your solar panel will not exceed 2 1/2 of amps of current, then the 3 amp version is fine. The 8 amp diode is acceptable for panels up to about 7 1/2 amps. Solar panels with more charge current then this would require a larger diode such as our 85 amp diode. This larger diode can be placed in-line with the common positive wire coming from your solar panels to your charge controller to handle multiple panels at one time. Please note: This larger diode may require a heat sink if they will be used for higher power applications (above 15 amps or so.) Click here for more info.
Do your controllers handle both wind and solar?
Yes, all of our controllers work for both wind and solar (Our relay/solenoid based controllers handle both at the same time). These controllers are primarily designed for turbines, but they also work for solar panels. Our solid stage controllers are perfectly suited to solar applications, yet are also quite capable as diversion controllers. Please see the manuals available on the item details page for wiring details.
Do you include a diversion load with your controller?
The Coleman Air controllers do not include any type of diversion load as these loads are very specific to your particular needs. Including a diversion load would cause the product to be very limited in scope and also increase the price. Controllers that include a diversion load often burn out quickly as quality cuts are made to the load itself.
Do I need a diversion load with my solar panels?
No, if you will be using our charge controllers with solar (PV) only you do not need a diversion load. If you will be using the controller with wind only (or also), you will need a diversion load.
Do I need a diversion load for my wind turbine?
Yes, Diversion controllers work by diverting excess energy from the wind turbine to a diversion or “dummy load”. This diversion allows the turbine to remain under a load at all times. A solar panel may be safely disconnected from the batteries, but an active wind turbine should never be disconnected from it's load (battery/diversion load). When a wind turbine is not loaded, it can easily speed out of control in high wind events, which can lead to catastrophic failure of the turbine as well as the possibility of damage and injury to other property and people. It is very important that your turbine has a very reliable load at all times.
Can I use a grid tie inverter as a diversion load?
Yes and No. This question is asked of us nearly every day as it seems like the perfect load, but..
The most common reason you need to divert the energy from your turbine is during high wind events (like thunderstorms) -- This is also the time the grid is most likely to fail. If the grid is down, so is your load, and the turbine spins out of control!
If you have a 2nd, very reliable load, then a grid tie inverter can be used as the primary load. You will need to controllers, one for the grid tie, the 2nd for the fail safe load.
Where does my inverter hookup to your controller?
Generally inverters do not hookup to charge controllers they hookup to the battery via a breaker or disconnect. The controllers job is to prevent battery overcharge. The inverters job is to convert D/C to A/C to run A/C appliances or send power back into the grid. The size of the controller does not affect the inverter and visa/versa -- they are independent.
If however, the inverter is to be used as a "Diversion Load" as discussed in the prior FAQ (and you understand the downside to doing this), then wire the micro grid-tied inverter in place of the "Diversion Load". In this case the inverter is the load for the controller. Please refer to the manual for your specific controller's for wiring details.
Please see the "Big Picture" for more information on hooking it all up.
Can I use my domestic hot water heater as a load?
Yes, but it really is not recommended unless you have two controllers. When a turbine is producing enough energy that it has fully charged the batteries and needs a diversion load, then that load must be there 100% of the time. Domestic hot water heaters cannot perform this task, since once the water is hot, the heating element will be disconnected.
Can I use two controllers together?
Yes, Two controllers can be used in a fail safe system to insure there is always a diversion load available. Simply set one controllers set point lower than the other. Use the lower set point for the unpredictable/part time load (like a hot water heater) and the higher set point controller for the 100% available load (a resistor bank)
Can I use a water pump or light bulb as a diversion load? Yes, but if the pump or light fails, so may your turbine. Heating elements and resistors are by far better choices for diversion loads.
How big does my diversion load have to be? Your diversion load should be 10 to 20 percent larger than your wind/hydro energy sources. You do not need to take into account any PV panels used as they are not routed through the diversion load. Please see the controller manuals for more information.
I have a 500 watt resistor, will this work? This is a big question. A resistor rated at 500 watts means it can handle 500 watts of electricity without damage to itself, but this does not mean it will use 500 watts in all systems (at all voltages.) The actual amount of power used by a resistor depends on Ohms law (E=I/R), where E = volts, I = Amps and R = resistance in Ohms. So to determine the amps used by a resistor we will divide the volts by the ohms.
Example: A 2 ohm resistor used in a 12 volt system (set to 14.5v), will yield 7.25A (14.5/2) or 105 watts (Volts x Amps), even if it says it's a 500 watt resistor. It would require a higher voltage (just under 32 volts) to bring this power dissipation up to 500 watts for a 2 ohm resistor! For a 12 volt system, you would need a 500 watt, 4/10 (.4) ohm resistor (good luck finding that dude), or five 100 watt, 2 ohm resistors in parallel to dissipate 500 watts.
With a solar system with batteries charged, diversion is not required, but what happens to the collected energy from the panels? where does it go?
On a solar system, the controller works as a disconnect controller and simply disconnects the panels until the battery voltage lowers about .5 to .7 volts (on a 12 volt system). Once the batteries reach this lower calculated point, the panels are again connected to the batteries (relays are disengaged), and the cycle continues. There is a programmatic delay to prevent quick relay cycling, yet the relays will engage and disengage as required to keep the batteries at a safe level. Note: Our solid state controllers may turn on and off several times a second.
I am thinking of using your controller with the Dummy Load being a second battery bank, what do you think?
A second battery bank is really not a good diversion load for two primary reasons.
- Hooking up a non-charged battery bank to a charged battery bank causes stress on both battery banks and especially the charged batteries. Also, if the 2nd battery bank is not in good condition, it simply wastes energy while stressing the good batteries.
- Once the 2nd battery bank is full (if it's a decent bank), then you don't have a load at all.
Can I hookup two turbines to one controller?
Yes, You can hookup as many as you like as long as the total energy from all turbines does not exceed the rating of the controller. Remember, the turbines hookup to the battery bank. The controller hooks up to battery bank and diversion load, so the controller does not care how many turbines (or PV Panels) are in the system.
Your diagram shows the turbine being hooked up directly to the battery. How can this work?
Wind turbines require a load on them at all times, so they need to be hooked up to either a battery or a matched load of some sort at all times. Once the battery is "full", then the controller "siphons" off the excess energy and sends it to a diversion load. This prevents battery overcharge. You may need a blocking diode/rectifier for your turbine (between the turbine and the battery), depending on the type of turbine you have. Please see the FAQ above for more specifics.
Why do some controllers show diagrams for hooking up the turbine to the controller, not the batteries.
Some diversion controllers have input terminals for the turbine. This is often misleading. These input terminals don't actually route any power through the electronics of the controller, they simply route the power directly from the turbine to the battery UNTIL the battery gets to a full state. At that point, the input power is diverted to the dummy load. So in essence, the turbine is hooked up directly to the batteries. The controller simply provides a termination point for the turbine. Some controllers like the Coleman Air C440-HVA do add additional functionality within the controller for the turbine, such as circuit overload protection, but even in this example, the turbine is still hooked up directly to the batteries through a breaker and shunt (for measuring amperage).
Since a turbine should see a load at all times, it is often better just to route the turbine to the batteries, then let the controller monitor the batteries and pull off any excess power as required to prevent battery overcharge.
What is the voltage input range of the Coleman Air controllers?
On the 12 and 24 volt models, the input range for the electronics is 10.5 volts to 35 volts continuous, 40 volts intermittently The input range on the relays should not exceed 40 volts.
On our 440 XL - the input range on the electronics is is 10.5 volts to 35 volts continuous, 40 volts intermittently . The solenoid can work with voltages up to 120 volts D/C or A/C
On our 440 HV series the the input range on the electronics is is 10.5 volts to 75 volts continuous, 100 volts intermittently . The solenoid can work with voltages up to 120 volts D/C or A/C
Our solid state controllers can handle larger voltages, please see the manuals for specifics.
I have a very small system at this time, will your controllers work with such a small amount of charge current?
There is no minimum size solar or wind turbine required for our controllers to function properly. Any of our controllers, even the larger ones will work with the smallest of systems.
My wind turbine puts out much more than 15 volts (for my 12 volt system), sometimes above 75 volts when the wind speed increases. Will your controller handle this?
All turbines put out more voltage (and current) when the wind speed increases. This is absolutely expected. But this voltage rise is reduced significantly when your turbine is hooked up to the battery bank. The battery bank "Clamps" the voltage to a much lower level. If you were to measure your wind turbines voltage without a load, you would notice that as the wind increased, the voltage would increase quite linearly. Basically, at twice the RPM, you would see about twice the voltage. This is what is referred to as "Open Circuit Voltage". When measuring voltage in this manner, there is no load and NO CURRENT (and thus no power). This voltage does not represent what the turbine will produce when it is actually hooked up to a battery bank or load.
Two distinct things change as soon as you place a real world load on your turbine (or hook it up to a battery).
- The turbine slows down as it now must actually move current through its stator and winding, this causes a electromagnetic feedback force (as the magnets produce current in the wires), this magnetic force resists the motion of the turbine -- So, it is now harder to turn and simply slows down.
- As the current increases the voltage decreases. Your turbine only puts out so many watts. Watts = amps x volts. (P = I x E ), so as the current increases, the voltage drops. Why is this important. When your battery is being charged, it is receiving a charge CURRENT. This current flows though the battery, charging the battery by actually changing the chemical composition of the battery. This charge current is the reason for the turbine to begin with. When the battery (or load) is receiving a current, then the voltage of the charge source (turbine) is reduced. If you were to short out the leads on the turbine, the current would increase to it's maximum value (if the blades did not come to a screeching halt), but the voltage would be near zero. The more battery or load, the lower the voltage will be, this is true in all alternator systems.
As long as the turbine is hooked up to a battery or a load, the voltage will be restricted greatly by the buffering capability of the battery and the current flow through load (battery or otherwise).
So, as long you hook up your turbine to a battery bank, the Coleman Air controller will never see a voltage rise large enough to cause any problems. When the voltage does rise, the diversion load will be engaged and the voltage will be reduced due to current flow that will be routed from the battery and or turbine to the diversion (or dummy) load.
Do the Coleman Air controllers downshift the voltage coming from the PV panels or wind turbine?
No, only MPPT controllers have such a feature. MPPT controllers work well for solar, but are not a good choice for wind power. Please see the discussion on this subject in our article entitled the Big Picture.
Generally you will not need to downshift the voltage from your turbine if is properly matched to your battery bank. A properly matched turbine/battery bank is when wind speeds in the range of 5 to 7 mph produce an open circuit voltage just above the nominal charge voltage of your battery bank.
For example, in a 24 volt battery based system, the turbine should produce 25 volts or so at around 5 to 7 mph wind speed. Therefor, when the wind speed increases a little more, the voltage will rise a little more (and of course the current will increase.) As the wind speed increases more, both the voltage and current will both increase, but the load on the turbine will become increasing greater. At some point (based on blade design, alternator design and many other factors), the turbine will either furl or the blades will stall (they cannot go faster.) If your turbine is properly designed, the turbine will be able to operate in the region without overheating. This then is the maximum sustained power that your turbine will be able to produce. At this wind range, the turbine is often putting out 1.5 times (or a little more) the voltage of the battery (even when loaded). So using our 24 volt example, you may see 36 volts or more coming into the batteries for short intervals. This is fine as long as you have installed a reliable and properly sized diversion load which will prevent the actual battery voltage from rising above the dump load trip point (about 28.8 volts by default.) The batteries are protected from over-voltage by the controller, since as soon as the battery voltage rises to the trip point, the controller will engage the relay and divert the excess current to the diversion load (this immediately reduces the battery voltage). Once the battery voltage drops by about 5 percent, the controller will disconnect the load and let the battery charge again. This cycle continues as long as the incoming power is great enough to bring the battery voltage up to the trip point. At no time however, was the voltage "Downshifted" by the controller. The normal functionality of wind turbines, controllers and batteries all work together to allow a highly variable voltage source to charge a much more finite battery bank.
What size wire do I need for my solar panels, wind turbine, charge controllers and batteries?
Please click here to see our Wire size calculator.
How do I set the voltage jumper selector on my controller?
Click to enlarge.
Most of our controllers have a jumper block that allows you to control the controller's sensing voltage. This is basically the voltage of your battery bank, that the controller will be monitoring. The jumper block is comprised of two columns of 4 rows of brass pins (8 pins total. See the diagram above). These rows of pins can be shorted across via a the jumper, which is a small black piece of plastic with a brass liner on the inside. These little jumpers can be lifted with your fingernails and inserted into any one of the rows (across two horizontal brass pins).
The image above shows the jumper has been set to the 24 volt position. This means the controller is currently set to operate with a 24 volt battery bank. Move the jumper down one position (lift it out and reinsert it), to use the controller in a 48 volt system. Move this same jumper up to the 1st position to use it in a 12 volt position. (Not all controllers have a 48 volt capability)
As shipped, the EDM jumper is hanging on one pin only. This means that the EDM mode has not been enabled. To enable EDM, lift the bottom jumper up, and insert it into the bottom two brass pins of the jumper block. Please see the manual for more information on the EDM mode.
All of the Coleman Air controllers require a battery bank; they will not work when hooked up directly to a wind turbine or solar panel, and most likely will be damaged very quickly if you attempt to hook up the controller to an energy source, and have not terminated it first to a battery.
