Starting with Battery Backup

[Logan005]

I am also a HAM and GMRS repeater operator. I have not found RFI interference from my solar setup, but then again I do not use typical HF bands most HAM's use. Many Hams do not ground their towers and associated equipment, because they believe a hard ground actually attracts lightning.

[Sunking]

Many Hams do not ground their towers and associated equipment, because they believe a hard ground actually attracts lightning.

There is some truth to that, but deadly ignorance in the assumption. An object does not need to be solidly or directly bonded to earth to attract and conduct lightning. It only has to be in proximity. Example a antenna mast bolted to the side of your home is more than enough. Lightning strikes the mast and finds it way to earth through your wood or brick siding, and your radio connected to the DC power supply. If you happen to be operating at such time then finds you to complete a circuit.

So the assertion hams do not earth ground equipment in their homes so they do not attract lightning is very foolish, not to mention does not comply with any known electrical codes or radio operating practices. I do it professionally and you can find a bit info on proper grounding of radio equipment on QRZ I wrote. They are the 3-part Stickies Grounding Do's and Don't

73's

KF5LJW

[Sunking]

I am also a HAM and GMRS repeater operator. I have not found RFI interference from my solar setup,

I do not doubt you one bit. RFI is not going to be much of an issue on repeaters as the frequency is too high unless you are running 10 and 6 meter ssb transponders. 2 meter and up FM is fairly immune from it. HF can be rendered useless especially if you are using inexpensive Chi-Com PWM controllers. Not only can it enter via power wiring, but also radiated and picked up by the antenna. I have a Midnite Solar Classic 150, and if I am not careful with wire routing and length, 40, 80, and 160 meters is useless in the afternoon when the controller is in PWM mode. Easy fix, disconnect the panels which I do with a switch to short out the panels. Problem solved. However I really have no use for the solar as the Astron keeps the batteries charged, the panels and charge controller just look cool and a conversation piece.

One thing I have noticed in California when I go there to visit from time to time, I fly into either LAX, SFO, SJO and then drive to the central coast of Morro Bay via 101. Commercial AM Radio and HF bands are rendered pretty much useless along the hwy in populated areas where power lines exist. There is so much Grid Tied Solar there, AM is pretty much wiped out from power line radiation. Nothing the FCC can really do about it now days as it would be politically incorrect for them to address the problem as it is only hams who complain and not the public. Hardly anyone listen to AM radio anymore except truckers.

[Living Large]

There is some truth to that, but deadly ignorance in the assumption. An object does not need to be solidly or directly bonded to earth to attract and conduct lightning. It only has to be in proximity. Example a antenna mast bolted to the side of your home is more than enough. Lightning strikes the mast and finds it way to earth through your wood or brick siding, and your radio connected to the DC power supply. If you happen to be operating at such time then finds you to complete a circuit.

So the assertion hams do not earth ground equipment in their homes so they do not attract lightning is very foolish, not to mention does not comply with any known electrical codes or radio operating practices. I do it professionally and you can find a bit info on proper grounding of radio equipment on QRZ I wrote. They are the 3-part Stickies Grounding Do's and Don't

73's

KF5LJW

I bought a used ROHN tower from a HAM in 1999 to mount tv and FM antennae on and he took the time to educate me on grounding. I live in an area with shale, and lightning strikes are frequent. I grounded that sucker as advised. I believe it was struck at least once, but caused no issue to my equipment as the energy went where desired. What did cause an issue was the downing of the WTC in 2001, which I was picking up signals from, 70 mi away. My former tower is now on an island in the Caribbean, being used by a guy who competes in HAM exercises as a hobby.

[Sunking]

My former tower is now on an island in the Caribbean, being used by a guy who competes in HAM exercises as a hobby.

I hate dem SOB contesters. They are the reason most leave the hobby. They have ZERO purpose in life. I jam them SOB's every chance I get.

[Mike90250]

Many Hams do not ground their towers and associated equipment, because they believe a hard ground actually attracts lightning.

That does not explain golf clubs in the hands of golfers.......

A "hard" ground is preferable, since you will know where 100% of the strike goes, 95% into the tower ground, 5% into the soft grounds within 100'

If you eliminate the "soft" grounds, have arresters on everything, you only have local EMP to deal with. And if your hard ground is a flagpole some distance away from your gear, you should be in great shape.

[n4pgw]

I have updated my system just a bit.

I disconnected the inverter from the battery and ran the battery wire to the Renogy Charge Controller battery input. I connected the inverter to the load output and I have nothing connected to the PV input of the Renogy.

My theory, based on the Renogy manual, is that if the battery voltage drops to 11.5, the Renogy will disconnect the load to save the battery.

I still have my Astron directly connected to the battery to charge it, but, even after leaving my computers running for two days, when I turned off the inverter, the only load to the battery, the Astron current drops to almost 9 amps. When all is powered up, the current rises to between 6-8 amps.

So, the power supply is actually powering the inverter since the battery is fully charged. I did a test by disconnecting the charger for an hour. That was long enough to drop the battery voltage a bit. When I powered up the Astron again, I was producing about 10 amps, 2 amps more than operating with a fully charged battery. The current draw continually dropped until it settled back at about 6 amps (my third monitor was turned off.)

I have not tested the Renogy under load with no charger yet. I don't like the computer being powered off by power failure. So I'll devise a load to draw the current and see if the Renogy disconnects the battery when the voltage drops.

I haven't decided what to do with the system after that test. I suppose I'll transfer more of my office load to the inverter. Maybe I can test my laser printer on it….??? I'll have to check the specs on it to see.

Until next time

Thanks again for all the input.

[Sunking]

I disconnected the inverter from the battery and ran the battery wire to the Renogy Charge Controller battery input. I connected the inverter to the load output and I have nothing connected to the PV input of the Renogy. My theory, based on the Renogy manual, is that if the battery voltage drops to 11.5, the Renogy will disconnect the load to save the battery.

You need to quit guessing. Bad mistake. Move your Inverter connection back to the battery terminals. The output on the controller is only for low power for something like an LED light. Your Inverter should already have its own built in LVD.

I still have my Astron directly connected to the battery to charge it, but, even after leaving my computers running for two days, when I turned off the inverter, the only load to the battery, the Astron current drops to almost 9 amps. When all is powered up, the current rises to between 6-8 amps.

So, the power supply is actually powering the inverter since the battery is fully charged. I did a test by disconnecting the charger for an hour. That was long enough to drop the battery voltage a bit. When I powered up the Astron again, I was producing about 10 amps, 2 amps more than operating with a fully charged battery. The current draw continually dropped until it settled back at about 6 amps (my third monitor was turned off.)

OK what is your point? That is exactly what is suppose too happen. The Astron PS does all the work. Solar is only there for show and tell rag chewing. Only thing you said that gets my attention is why are your drawing 9 amps with everything turned off. Does your Inverter burn 140 watts just sitting there doing nothing?

[Living Large]

You need to quit guessing. Bad mistake. Move your Inverter connection back to the battery terminals. The output on the controller is only for low power for something like an LED light. Your Inverter should already have its own built in LVD.



OK what is your point? That is exactly what is suppose too happen. The Astron PS does all the work. Solar is only there for show and tell rag chewing. Only thing you said that gets my attention is why are your drawing 9 amps with everything turned off. Does your Inverter burn 140 watts just sitting there doing nothing?

I believe that is a typo - should be 0.9A. That is just a guess.

[Sunking]

I believe that is a typo - should be 0.9A. That is just a guess.

I hope so.

[n4pgw]

You need to quit guessing. Bad mistake. Move your Inverter connection back to the battery terminals. The output on the controller is only for low power for something like an LED light. Your Inverter should already have its own built in LVD.

The inverter LVD only triggers at 10.5 volts, not 11.5 volts.

It's a 30 amp solar controller, it can't handle that much on the load side?

Only thing you said that gets my attention is why are your drawing 9 amps with everything turned off. Does your Inverter burn 140 watts just sitting there doing nothing?

Typo-- Should be "0" amps.

I have separate wires going to and from the battery. The positive terminal now directly feeds everything through a shunt resistor so I can measure the current and voltage on a digital meter I have. I run the wire for the meter later this week when it isn't raining.

I just discovered that I had my Astron disconnected and it's been that way for 2 hours. The inverter showed 11.8 volts when I discovered it and plugged the Astron back in. The Astron current jumped to 20 amps, but in just one to three minutes, it dropped back to 12 amps where it is now. The inverter shows voltage at 12.4 and rising slowly. It will eventually make its way back up to 12.8 where it sits when I have a load on it. The astron will drop current to about 6 amps and will stay there until I turn off the inverter again. It's already down to about 11 amps now.

From the Renogy instruction sheet:

6. Connect the DC Load (Optional)
Connect 12 VDC ... loads to these terminals. The maximum rated current is ... 30 amps for the WPM30CC. However, it is recommended that the loads do not exceed 80% of this rating. If the orange or red LED battery indicator light turns on, the battery capacity is low and needs to be charged before using any connected loads again. Do not connect devices such as power inverters, high power DC Motors/pumps or other DC electronics with heavy electrical load that exceed the charge controller ratings.

Battery Parameters:
Load Disconnect: 11.1v
Load Reconnect: 12.6v
Equalization Voltage (30 Minutes): 14.6v
Boost Voltage (30 Minutes): 14.4v
Float Voltage: 13.6v
Battery Type: Sealed Lead Acid and Flooded

According to what I just read, as long as I primarily stay below 24 amps, (over 30 amps the controller will auto-disconnect the load) I should be good. Does that sound right?

I believe that is a typo - should be 0.9A. That is just a guess.

Yes, typo. The needle only drops from the top of the black bar at 0 to the bottom of the black bar at 0 when I turn off the supply (as opposed to being on with full charge and no load.) It's got to be 1/4th or less amps.

[n4pgw]

The image is the back page of the controller manual. Another page explains that it will shut off if the load is over 1.25 * rated amps for 60 seconds or 1.5 * the rated amps for 5 seconds.

It looks like the solar load should not exceed 24 amps (80% of 30 amps) and the load should not exceed 100% (30 Amps).

I do believe in safety factors, such as not to pull the full 35 amps continuously on the Astron, even though it is rated for that, and I would probably still keep to the 24 amps for the load on the charge controller.

If what I read is correct, I should be quite safe. I can charge the battery at up to 30 amps through the #10 wire going from charger to battery, and I should be able to draw up to 30 amps (typically 24 amps) from the charge controller load port.

[Sunking]

The LOAD TERMINAL on the Controller should not be used. It can only handle a very small load current for something like LED lights. Disconnect from and it never use it again. Connect your Inverter directly to the BATTERY TERM POST along with your Astron. PS. If not you will burn up your Controller LOAD PORT. Look it up as it is likely fused for 10 amps.

Go read Step 4 in your Quick Start Directions

4. Connect the DC Loads (optional) : Connect 12VDC (12V systems) or 24VDC (24V systems) loads to these terminals. The maximum rated current is 10 amps for the PWM10CC and 30 amps for the PWM30CC. However, for safety, it’s recommended that the loads do not exceed 80% of this rating. If the orange or red LED battery indicator light turns on, the battery capacity is low and needs to be charged before using any of the connected loads again.Do not connect devices such as power inverters, high power DC motors/pumps or other DC electronics with heavy electrical load that exceed the charge controller ratings.

You have not stated what size Inverter or Radio TX power levels are. At 26 amps means the Inverter can be no larger than 300 watts, and any 100 watt Transceiver draws 25 amps. Operate both at capacity and you wil have SMOKE. The LOAD TERMINAL on your Controller is a useless Bell and Whistle you have no use for.

[PNjunction]

The inverter LVD only triggers at 10.5 volts, not 11.5 volts.

Yep, and "saving the battery" in this case means saving you from hugely degenerative *chemical* degradation. BUT, you are still killing cycle life badly if you get to this point.

Essentially what happens when you deep-discharge is that the acid in the electrolyte is largely water, and grid-corrosion escalates rapidly. That, along with a large amount of sulfation - which if left too long hardens for a double-whammy, buckling / warping the plates, and so forth. Do NOT rely on the LVD, at either 10.5 or 11.5v as your daily discharge recovery routine. It is a dead-man switch mainly.

It's a 30 amp solar controller, it can't handle that much on the load side?

Controller are rated for the solar INPUT, since the output is ideally being drawn from the battery directly. LOAD terminals are value-added low-current options for dinky stuff. Dinky stuff, like the lights in your swr bridge.

I have separate wires going to and from the battery. The positive terminal now directly feeds everything through a shunt resistor so I can measure the current and voltage on a digital meter I have. I run the wire for the meter later this week when it isn't raining.

Are you using the right gauge to avoid excessive voltage drop? Are you measuring voltages *at the battery terminals*, and not just at the output of the controller? Consult solar wiring charts to stay under 2% drop. Note the difference between "one way" and "two way" charts - ie point to point, or out-and-back lengths.

And we still don't know what batteries you are running, unless I missed it.

A lot of stuff is getting thrown out to the wall to see if it sticks here instead of getting all the variables nailed down first. Makes for super-lengthy threads.

[n4pgw]

The LOAD TERMINAL on the Controller should not be used. It can only handle a very small load current for something like LED lights. Disconnect from and it never use it again. Connect your Inverter directly to the BATTERY TERM POST along with your Astron. PS. If not you will burn up your Controller LOAD PORT. Look it up as it is likely fused for 10 amps.

Go read Step 4 in your Quick Start Directions

4. Connect the DC Loads (optional) : Connect 12VDC (12V systems) or 24VDC (24V systems) loads to these terminals. The maximum rated current is 10 amps for the PWM10CC and 30 amps for the PWM30CC. However, for safety, it’s recommended that the loads do not exceed 80% of this rating. If the orange or red LED battery indicator light turns on, the battery capacity is low and needs to be charged before using any of the connected loads again.Do not connect devices such as power inverters, high power DC motors/pumps or other DC electronics with heavy electrical load that exceed the charge controller ratings.

You have not stated what size Inverter or Radio TX power levels are. At 26 amps means the Inverter can be no larger than 300 watts, and any 100 watt Transceiver draws 25 amps. Operate both at capacity and you wil have SMOKE. The LOAD TERMINAL on your Controller is a useless Bell and Whistle you have no use for.

The LOAD TERMINAL on the Controller should not be used. It can only handle a very small load current for something like LED lights. Disconnect from and it never use it again. Connect your Inverter directly to the BATTERY TERM POST along with your Astron. PS. If not you will burn up your Controller LOAD PORT. Look it up as it is likely fused for 10 amps.

According to Renogy, the load port is good for 30 amps, and even more for a short period before turning it off. The Astron is fused at 10 amps on the ac side. (Actually, it is fused at 7 amps since I didn't have 10 amp fuse.)

Go read Step 4 in your Quick Start Directions

4. Connect the DC Loads (optional) : Connect 12VDC (12V systems) or 24VDC (24V systems) loads to these terminals. The maximum rated current is 10 amps for the PWM10CC and 30 amps for the PWM30CC. However, for safety, it’s recommended that the loads do not exceed 80% of this rating. If the orange or red LED battery indicator light turns on, the battery capacity is low and needs to be charged before using any of the connected loads again.Do not connect devices such as power inverters, high power DC motors/pumps or other DC electronics with heavy electrical load that exceed the charge controller ratings.

I have the 30 amp charge controller, so I should be safe up to 24 amps.

You have not stated what size Inverter or Radio TX power levels are. At 26 amps means the Inverter can be no larger than 300 watts, and any 100 watt Transceiver draws 25 amps. Operate both at capacity and you wil have SMOKE. The LOAD TERMINAL on your Controller is a useless Bell and Whistle you have no use for.

The inverter is rated for 1000 watts/2000 surge. While I realize it {can} pull more power, I am only running a limited load below 24 amps at this time. (I'll change the controller or layout if I increase the load.)

The radio draws less than 10 amps, and is directly connected to the power supply which is directly connected to the battery. It is not connected through the solar controller.

My battery is a 105 AH marine battery. Currently, I only have one. I am planning on setting up a couple of 100 watt solar panels this spring and use this battery as my UPS for my computer station.