Elk p212s voltages

[mikefamig]

I installed an Elk p212s in my garage with only a DBH and input expander so far. I =t has an 18AH Elk battery. Everything seems to be running fine but when I noticed that the battery voltage will sit around 13.9 volts and periodically ramp up to over 16 volts. The battery boils a little and after a short while the voltage returns to about 13.9 volts.
 
Is this normal? The ps212s is enrolled as keypad 15 and it's input zone is defined as power supervisory. I'm out of ideas. I DID notice that the p212s instructions say to not use aq battery larger than 12 amp hours. Can this be causing this symptom?
 
Mike.

 

[Del91574]

A larger than maximum spec battery will manifest other ways, but a battery boiling over is no bueno. 14V would constitute overcharging which is why the battery is experiencing issues. Voltage should really be no more than 13.

 

[RAL]

A SLA battery is sealed and should not out-gas under normal circumstances.  That only happens if the battery is being overcharged.  The voltage at the battery should not go above 14V, and 16V is definitely too high.  From what you describe, it does sound like the battery is being overcharged.   If you haven't already done so, shut it off!
 
I don't think this has anything to do with how you've defined the P212S to the M1.  The charger can operate without any databus connection at all.  When it is connected to the databus, the M1 isn't controlling the voltage output or the battery charging. 
 
From a strictly theoretical point of view, a battery charger needs to limit the current that it delivers to a battery when it is charging.  A battery, whether it is 12 Ah or 18 Ah, looks like a dead short to the charger, since (good) batteries have very low internal resistance.   So it really shouldn't matter how large the battery is - a properly designed charger limits its output current and wouldn't be damaged by a large battery.  It would just take longer to charge it.  
 
That said, DEL and some others say they have seen cases where too large a battery did damage a charger.   That's difficult to explain, unless the charger contained some marginal components that couldn't handle the longer time required to charge a large battery.   Actual experience tends to trump theory!

 

[mikefamig]

Yes I have turned the entire system off. So you guys are saying that the p212 is at fault, no?

 

[RAL]

Yes, it sounds like there is something wrong with the P212S.  It shouldn't be charging the battery at that high a voltage.

 

[mikefamig]

I understand that the control monitors both battery voltage and AC voltage so I thought that it might also regulate the 12 output voltage.I hope that I can get the part warrantied.
 
Mike.

 

[RAL]

From what you have described, I don't think anything you have done caused the problem.  I think all you need to do is tell them that it is overcharging the battery and that should be good enough.

 

[mikefamig]

I just did some snooping with a volt meter and found something interesting.
 
1 My AC outlet is 119 volts
2 my elk 16.5ac volt transformer is at 19ac volts which is translating into ~14dc volts at vaux and data bus voltage
3 my Honeywell transformer is also around 19ac volts but translating into 16+ dc output voltages at the battery charger and data bus supply voltage.
 
The transformer outputs were done both connected to the system and standing alone.
 
So my question now is has anyone ever put an ac volt meter on their trg1640 transformer to see what it is actually supplying?
 
Mike.

 

[RAL]

On my system, I measure 19.5V on the TRG1640 transformer with no load connected.   With a load of 1.9A, this drops to 19.2V.   
 
The voltage at the battery terminals is 13.5V.
 
The power supply shouldn't be bothered by a slightly higher AC input voltage (19V vs 16V).  It's job is to take an input voltage that can vary (within reason)  and convert it to DC and regulate it to maintain a constant output voltage.
 
I can't explain why you see a difference on the output with the two transformers when both seem to be providing 19 VAC to the input.

 

[Del91574]

I just did some snooping with a volt meter and found something interesting.
 
1 My AC outlet is 119 volts
2 my elk 16.5ac volt transformer is at 19ac volts which is translating into ~14dc volts at vaux and data bus voltage
3 my Honeywell transformer is also around 19ac volts but translating into 16+ dc output voltages at the battery charger and data bus supply voltage.
 
The transformer outputs were done both connected to the system and standing alone.
 
So my question now is has anyone ever put an ac volt meter on their trg1640 transformer to see what it is actually supplying?
 
Mike

I'm reading this and it sounds like you're comparing the supply to the panel itself....two different items altogether.
 
The AC and transformer values are close enough in spec that any difference is nominal. A 16.5 VAC transformer will kick out around 18-19VAC under normal circumstances (usually about 20% over rating). The VA values are inconsequential at this point, assuming the 5VA difference....we're only talking a basic charging circuit with nothing connected to the supply at this point, right?

What you're experiencing on the 212 is symptomatic of a bad voltage regulator or output on the charger itself. Without going and looking at the ones I have around here or in the truck, I don't know off the top of my head if there's a trimpot on them like Altronix has.
 
Let's do some basic...with the unit disconnected from the panel, what is the DC output of the supply's terminals? Anything above 13 is bad. With the battery disconnected, what is the output on the charging circuit? Shouldn't be much past 13 or 13.5V.  Finally, with the battery you'd need to perform voltage tests and amperage tests to really determine what is going on.
 
With a normal battery, charged to spec (13.5~12.5VDC, no load) you should see approximately the same value on the supply with the AC disconnected.
 
At this point, with the symptoms so far, I'd RMA the unit and dispose of the battery....it's already been damaged.

 

[mikefamig]

I'm reading this and it sounds like you're comparing the supply to the panel itself....two different items altogether.
 
The AC and transformer values are close enough in spec that any difference is nominal. A 16.5 VAC transformer will kick out around 18-19VAC under normal circumstances (usually about 20% over rating). The VA values are inconsequential at this point, assuming the 5VA difference....we're only talking a basic charging circuit with nothing connected to the supply at this point, right?

 
I have tested the transformers both connected and disconnected from their respective loads. The elk transformer is used with the control and the honeywell transformer is being used with the p212s.
 

What you're experiencing on the 212 is symptomatic of a bad voltage regulator or output on the charger itself. Without going and looking at the ones I have around here or in the truck, I don't know off the top of my head if there's a trimpot on them like Altronix has.

 
I don't believe that there is any adjustment for the outputs but I will take a closer look at the board.
 
 

Let's do some basic...with the unit disconnected from the panel, what is the DC output of the supply's terminals? Anything above 13 is bad.

 
I don't understand what you mean by "unit". The p212s is being used with a DBH and an input expander at this point and the voltage is higher than 13vdc with no load connected to it. I forget the exact numer but I think it was at least 14vdc.

With the battery disconnected, what is the output on the charging circuit? Shouldn't be much past 13 or 13.5V.  Finally, with the battery you'd need to perform voltage tests and amperage tests to really determine what is going on.

 
Again, it is not much past 13.5 and I believe it is around 14vdc and goes as high as 16vdc with the battery connected and charging.

With a normal battery, charged to spec (13.5~12.5VDC, no load) you should see approximately the same value on the supply with the AC disconnected.

 
The batery measures 13.9 volts with no load and the p212s outputs will get down to that same level when it is all hooked up and running. This wouldn't bother me but the charger is going up and down between 14 volts and 16 volts periodically.

At this point, with the symptoms so far, I'd RMA the unit and dispose of the battery....it's already been damaged.

Why do you say that the batery has been damaged? All of it;s cells are charged and it's outputting 13.9 volts with no load.
 
Mike.

 

[mikefamig]

Today I'm going to connect the Elk trg1640 transformer to the p212s and see if it makes any difference. I can't imagine why it would matter but it is possible that it has circuitry that interacts with the p212s in some way.
 
Here's a quote from the p212s speications:
 
Innovative EBT - Elk Battery Technology circuit provides maximum battery life
 
-  Controlled  charge  ramp  and  maintenance  algorithm
- Low Battery cut-off protects battery from deep discharge
 
Mike.

 

[mikefamig]

The instructions for the p212s state that the +12vdc lead from the elk control is connected to a spare connector on the p212s and serves no purpose. Instead of connecting it to the "spare" terminal I did not connect it at all. Can this be a problem and maybe it needs to be connected?
 
Mike.

 

[RAL]

The instructions for the p212s state that the +12vdc lead from the elk control is connected to a spare connector on the p212s and serves no purpose. Instead of connecting it to the "spare" terminal I did not connect it at all. Can this be a problem and maybe it needs to be connected?

 
I don't think there is any connection from the Spare terminal to any other components on the circuit board at all, so it shouldn't matter whether you connect the wire to it.
 

The batery measures 13.9 volts with no load and the p212s outputs will get down to that same level when it is all hooked up and running. This wouldn't bother me but the charger is going up and down between 14 volts and 16 volts periodically.

 
The voltage on the battery should NEVER get as high as 16V.  The fact that it is says there is something wrong with the charging circuit in the P212S.  The outputs of the P212S that go to the load are driven by different circuitry within the P212S.  So even if the load output reads 13.9V, if you are seeing 16V to the battery, it means something is wrong with the charging circuit.
 
 

Why do you say that the batery has been damaged? All of it;s cells are charged and it's outputting 13.9 volts with no load.

 
If the battery was out-gassing, that indicates that some of the electrolyte inside has boiled away, and that damages the battery. 
 
[Edit]
 
To determine the extent of the damage, you would need to put it through a test under load to see how long it can power the load.  This requires careful monitoring of the voltage output of the battery to make sure it doesn't drop too low (below 10.5V).   The P212S contains low voltage cutoff circuitry that does this. 

 

[Del91574]

I have tested the transformers both connected and disconnected from their respective loads. The elk transformer is used with the control and the honeywell transformer is being used with the p212s.
 
 
I don't believe that there is any adjustment for the outputs but I will take a closer look at the board.
 
 
 
I don't understand what you mean by "unit". The p212s is being used with a DBH and an input expander at this point and the voltage is higher than 13vdc with no load connected to it. I forget the exact numer but I think it was at least 14vdc.
 
Again, it is not much past 13.5 and I believe it is around 14vdc and goes as high as 16vdc with the battery connected and charging.
 
The batery measures 13.9 volts with no load and the p212s outputs will get down to that same level when it is all hooked up and running. This wouldn't bother me but the charger is going up and down between 14 volts and 16 volts periodically.
Why do you say that the batery has been damaged? All of it;s cells are charged and it's outputting 13.9 volts with no load.
 
Mike.

Mike, you're reading way too much into this.
 
A transformer is a transformer is a transformer...only difference is how close to spec the output is and what the VA rating is....and in the case of the two units, it's close enough to really not matter in this case. The only variable is whether or not the secondary is fused or PTC protected.
 
Comparing the panel to the 212S is not a valid test.
 
Simplify. Remove the panel from the equation. Run the 212 as it's own standalone power supply and test from there. The connection to the panel is inconsequential and not important...it's only used to report to the M1 and/or allow the output to be triggered, the supply should run irregardless of a connection to the host panel. You're worrying and reading too much into it at this connection, same with the spare terminal and wiring. It's not part of the equation.
 
The transformer(s) are fine in this case, nor is there a problem with the wall voltage. This is not part of the equation that needs to be investigated further. If the supply couldn't keep up with the load or charge the battery, then you'd have an idea to look here, but not in this case.
 
The battery you have has 2 problems....first, it's not within spec of the maximum size the charger supports, so it may have damaged the supply (we don't know). Second, the battery, by heating up and boiling over, is damaged and not salvagable. The only thing that stopped it from splitting open or exploding are the vents. It is garbage now.
 
If your aux power output is above 12.5 volts +/- a couple of tenths, with no battery connected, the supply portion is OK.
 
If your charging voltage is above 13.5, that's suspect. With a smaller battery within spec of the overall load (IE: 7ah) are the voltages/amperages within spec? Remember, Ohm's law applies...amperage goes down, voltage goes up. So if your unit can't keep up with the amperage output to charge the load, the voltage is going to inversely increase. The resistance really isn't changing in this application.
 
Realistically, I'd say three things are true in this case....the battery is oversized which may have contributed to damage on the charger (they put the limit for a reason). At minimum the supply is not going to perform correctly on it's "smart" portion. Second, the battery is damaged and further usage is going to damage the components connected to it, so it's time to send it off to the scrapper. Third, the supply is already suspect, whether or not it worked properly before the battery connection can't be determined, but how it's performing at this point is suspect.
 
Pull the bandaid off and RMA the supply and buy a new battery within spec.