Progressive Dynamics PD9270. What voltage is required to activate boost mode?

[checkthisout]

I posted this question on an RV forum as well has sending it to Progressive dynamics. My generator starts by itself based on voltage and is controlled remotely. I am currently 150 miles away. My progressive dynamics battery charger charges in "normal" mode (13.5 volts) when I let battery voltage fall to 12 volts so my generator will have to run for days in order to get a full charge back into the batteries.

I want it to start in boost mode (14.4 volts) but do not know how low the battery voltage has to drop in order for that occur. When in person and when the batteries are under high draw, I set the generator to startup at 11.8 volts and this always seem to activate boost mode but I don't want to have to let the battery voltage drop that low when I have slow draw (cameras security system etc) when I am not there in order for the charger to have to start in boost mode.

Thanks.

[Mike90250]

Define what you think Boost mode is.
Lead acid battery common terminology is Bulk (1), Absorb (2), and Float. Every couple months, an Equalize cycle is needed. Absorb has to complete before EQ can start
also see the first chart here https://batteryuniversity.com/articl...ging-lead-acid

MS_charge_stages.png

[checkthisout]

Define what you think Boost mode is.
Lead acid battery common terminology is Bulk (1), Absorb (2), and Float. Every couple months, an Equalize cycle is needed. Absorb has to complete before EQ can start
also see the first chart here https://batteryuniversity.com/articl...ging-lead-acid

MS_charge_stages.png

It's what Progressive Dynamics calls boost mode which is (boost) 14.4 volts which then drops to (normal)13.6 and then to (storage)13.2.

I have my generator set to start at 12.2 but the charger isn't going to 14.4 at this battery voltage when I start the Gen and I want it to.

I did get my answer from PD though. I have to allow the voltage to drop to 11.9 in order for boost mode to be activated at Gen start. This is fine when I am at my cabin and using the system but not good for low draw that occurs when I am not there. It takes forever to being the batteries back up at that voltage.

I am rigging up a remote switch to activate 14.4 v charging remotely.

[Mike90250]

I really hate it, when some company has to distinguish itself, by inventing some non-standard way to do things everyone else does. Sorry you have to be the discover of oddities....

[Ampster]

I really hate it, when some company has to distinguish itself, by inventing some non-standard way to do things everyone else does. Sorry you have to be the discover of oddities....

I hate it also. I prefer to use the terms Constant Current and Constant Voltage. Every one of those non standard terms is either a form of CC or CV. They can be measured and expressed in electrical terms of Voltage and/or Amps.
Sunking does a good job of explaining some of these terms in one or more of the Stickies.

[checkthisout]

Well, it worked. I let the voltage drop the 11.9 and the charger changed to 14.4 once power was applied to it. Kind of a painful process this off-grid stuff....especially for someone like me who dives then looks....

[Mike90250]

Well, it worked. I let the voltage drop the 11.9 and the charger changed to 14.4 once power was applied to it. Kind of a painful process this off-grid stuff....especially for someone like me who dives then looks....

That's sometimes called the "Rebulk Voltage" Adjustable on some controllers

[checkthisout]

I hate it also. I prefer to use the terms Constant Current and Constant Voltage. Every one of those non standard terms is either a form of CC or CV. They can be measured and expressed in electrical terms of Voltage and/or Amps.
Sunking does a good job of explaining some of these terms in one or more of the Stickies.

I don't think about it that way. The charger commands 14.4 volts and ramps up the power output to the coil until that voltage is achieved. The limiting factor being the wattage limit of the charger being hit before the target voltage is achieved.

The next mode is 13.6 volts and same deal.

The next mode is 13.2 volts and same deal.

At no time is the charger controller the amps flowing.

[Ampster]

I don't think about it that way.

Whatever works for you is the best way to understand it.

The charger commands 14.4 volts and ramps up the power output to the coil until that voltage is achieved. The limiting factor being the wattage limit of the charger being hit before the target voltage is achieved.........
At no time is the charger controller the amps flowing.

If the charger is limited by Wattage then technically all it can do is control the Amps and voltage so that its Wattage capacity is not exceeded since Watts equals Volts times Amps.
However, as Sunking explains in one of the Stickies, in the case of a solar charge controller when power from the panels is less than the capacity of the controller, voltage will not be greater than the user setting or what the battery will except up to that user setting. In that case the Amps would be limited by the output power of the panels. That is an exception to Constant Current charging.

[checkthisout]

Whatever works for you is the best way to understand it.

If the charger is limited by Wattage then technically all it can do is control the Amps and voltage so that its Wattage capacity is not exceeded since Watts equals Volts times Amps.
However, as Sunking explains in one of the Stickies, in the case of a solar charge controller when power from the panels is less than the capacity of the controller, voltage will not be greater than the user setting or what the battery will except up to that user setting. In that case the Amps would be limited by the output power of the panels. That is an exception to Constant Current charging.

I guess I need help understanding. What does constant current mode look like on a charger?

I understand constant voltage. The charger ramps power until it reaches its target voltage.

What does a charger do in "constant current" mode?

I can understand a charger limiting its output wattage but then wouldn't this be a function of it's target voltage?

[Ampster]

I guess I need help understanding. What does constant current mode look like on a charger?

I understand constant voltage. The charger ramps power until it reaches its target voltage.

What does a charger do in "constant current" mode?

I can understand a charger limiting its output wattage but then wouldn't this be a function of it's target voltage?

As I mentioned the Sunking Stickies explain this well and that is how I took my knowledge of Ohms law and building Heathkits in the fifties to a practical knowledge on this subject.

Fundamentally any device can only measure current and voltage. Power in Watts is a calculation based on Watts = current times voltage. A charger calculates power based on the above formula but it can only control voltage and current. The method a charger uses to control power is to take the voltage from the battery and supply current up to the current limit set on charger. That is the Constant Current mode because the battery will only accept voltage based on its State of Charge. In that mode the battery controls the voltage. With a constant current supplied by the charger the power ramps up as the battery accepts more voltage until the charger hits the Constant Voltage set point. Then the charger goes into Constant Voltage mode. The only way the charger has to prevent more voltage going into the battery is to ramp down the current to keep the voltage Constant. It is simple physics and two variables. Read the Stickie to see Sunking's explanation. He may use different terminology but the physics is the same.

[checkthisout]

I pulled the "charge wizard pendant" apart. The pendant consists of a button and indicator light and length of cord for remote mounting. A single tap the button puts the charger into "boost" (14.4) mode. Holding the button allows you to toggle through the 3 modes.

It's a 4 wire lead but only 3 of the leads are used. One supplies power to the pendant. Pressing the button takes power and applies to the 2nd lead and the 3rd lead is grounded by the charger and controls the indicator light.

I broke out the harness and ran the positive lead and button lead and paralleled them to a Sonoff relay that I can control via an app on my phone.

I can now toggle the charger through the different modes via internet so problem solved!

[checkthisout]

As I mentioned the Sunking Stickies explain this well and that is how I took my knowledge of Ohms law and building Heathkits in the fifties to a practical knowledge on this subject.

Fundamentally any device can only measure current and voltage. Power in Watts is a calculation based on Watts = current times voltage. A charger calculates power based on the above formula but it can only control voltage and current. The method a charger uses to control power is to take the voltage from the battery and supply current up to the current limit set on charger. That is the Constant Current mode because the battery will only accept voltage based on its State of Charge. In that mode the battery controls the voltage. With a constant current supplied by the charger the power ramps up as the battery accepts more voltage until the charger hits the Constant Voltage set point. Then the charger goes into Constant Voltage mode. The only way the charger has to prevent more voltage going into the battery is to ramp down the current to keep the voltage Constant. It is simple physics and two variables. Read the Stickie to see Sunking's explanation. He may use different terminology but the physics is the same.

Weird. I think the bulk phase is just the charger commanding higher voltage rather limiting current on the control side to whatever the max rating of the charger is. If the charger is 1000 watts, then that's 69.4 amps at 14.4 volts. If the battery terminal voltage is low, then even though the commanded voltage is 14.4, the charger may only only be able to reach say 13 volts in which case the charger will be flowing 77 amps or 1000 watts.

In the above case, lets pretend our charger is commanding 13 volts. Well, it still flows 77 amps because even though it is now in "constant voltage" rather than constant current mode. I don't see any difference in any of these modes. The only reason the amperage or "current" changes is due to the fact that the battery terminal voltage and commanded voltage from the charger are different.

All 3 modes "bulk, absorption and float" all have the full output of charger available and the charger never limits the amperage flowing to the battery, it only limits the amount of current it will draw from it's power supply.

[Ampster]

Weird. I think the bulk phase is just the charger commanding higher voltage rather limiting current on the control side to whatever the max rating of the charger is. If the charger is 1000 watts, then that's 69.4 amps at 14.4 volts. If the battery terminal voltage is low, then even though the commanded voltage is 14.4, the charger may only only be able to reach say 13 volts in which case the charger will be flowing 77 amps or 1000 watts.

It is not weird to me, it is just simple physics as explained in the Stickies. Most chargers have a maximum current setting and that is what is usually used in Bulk (Constant Current) phase of charging. When the battery reaches the Absorb (Constant Voltage) setting, the charger begins reducing the current to keep the voltage from rising above the setting.

In the above case, lets pretend our charger is commanding 13 volts. Well, it still flows 77 amps because even though it is now in "constant voltage" rather than constant current mode. I don't see any difference in any of these modes. The only reason the amperage or "current" changes is due to the fact that the battery terminal voltage and commanded voltage from the charger are different.

I encourage you to read the stickie and use the terminology commonly used to describe what chargers do. I am unfamiliar with the term of a charger "commanding" voltage or current. The battery determines voltage based on its state of charge. In your example, if the charger is set at 13 volts and the battery is at 12 volts then it is possible the charger could output its maximum current and the current would begin to taper off as the battery approaches 13 volts and would continue to be reduced as the voltage remains at 13 volts.

All 3 modes "bulk, absorption and float" all have the full output of charger available and the charger never limits the amperage flowing to the battery, it only limits the amount of current it will draw from it's power supply.

A charger is essentially a power supply and many people use power supplies to charge batteries. I believe the charger limits the current in both Absorb and Float mode. They are both Constant Voltage modes or phases. The only difference between Absorb and Float is that Float uses a much lower current and the voltage setting for Float is lower than the Absorb mode. Absorb usually has a timer setting or a finishing Amps setting that turns off the power when that setting is reached. Float is often used with Pb batteries to offset self discharge.

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[checkthisout]

It is not weird to me, it is just simple physics as explained in the Stickies. Most chargers have a maximum current setting and that is what is usually used in Bulk (Constant Current) phase of charging. When the battery reaches the Absorb (Constant Voltage) setting, the charger begins reducing the current to keep the voltage from rising above the setting.


I encourage you to read the stickie and use the terminology commonly used to describe what chargers do. I am unfamiliar with the term of a charger "commanding" voltage or current. The battery determines voltage based on its state of charge. In your example, if the charger is set at 13 volts and the battery is at 12 volts then it is possible the charger could output its maximum current and the current would begin to taper off as the battery approaches 13 volts and would continue to be reduced as the voltage remains at 13 volts.

A charger is essentially a power supply and many people use power supplies to charge batteries. I believe the charger limits the current in both Absorb and Float mode. They are both Constant Voltage modes or phases. The only difference between Absorb and Float is that Float uses a much lower current and the voltage setting for Float is lower than the Absorb mode. Absorb usually has a timer setting or a finishing Amps setting that turns off the power when that setting is reached. Float is often used with Pb batteries to offset self discharge.

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When referring to "constant current", where in the system is current being measured?