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AIMS Power 12V AC Converter

dbrfan

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Joined
Mar 17, 2021
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10
Hi,
I am building a 12V 160Ah Lifepo4 battery with a Daly 200A BMS and recently purchased the AIMS Power 12V converter/charger to charge the battery. The battery and BMS appear to be functioning correctly with a current SOC of 13.2V. The positive cable is connected directly from the charger to the batteries positive post. The negative cable is routed from charger to the P- cable of the BMS to complete the circuit. I connected the battery cables to charger prior to plugging it in, then turned it on, but the red fault light is on. It remains on after unplugging the charger as well.

I have the dip switches both toggled to the "0" and have adjusted the current control from 0 to 100, but nothing changes. Do yall have any insight on what is wrong?

I'll have to wait until the weekend to try a couple of other things including, connect charger to other AGM battery as well as remove BMS from the Lifepo4 battery and connect directly to the POS/NEG terminals....not sure what else to do. The BMS has a 100A charge rating. IMG_6167.jpg
 
Did you use resistor (47 Ohms 10W should be fine) to precharge the capacitors bank in the AIMS Inverter charger to limit the inrush current first before directly connecting the cables? The BMS may have been tripped due to over current condition, you can try resetting the BMS.
 
This appears to be a common-port Daly BMS. Do not connect the AIMS directly to the Battery "-" terminal! After eliminating any Voltage differential between the "B-" and "P-" wires of the BMS, using DVM set to measure OHMS (and not volts, and not shorting it out!) you should connect the charger "-" battery output terminal to the "P- terminal (on a grounding bus bar, along with loads and maybe going through a coulomb-counter meter before reaching "P-").

I have no idea what the DP switch settings are on the AIMS. My advice is to be sure that the BMS is functional (via bluetooth or UART), and then connect the negative leads properly. (Including "P-", after settling the voltage against B- by using the DVM reading "ohms".) THEN connect your "main" battery "+12V power lug into the charge and load bus (through a fuse block not yet connected, or circuit breaker not yet activated).

If your BMS needs to be reset, do that now.

Connect your AIMS charger to the "12V" bus and set your DP switches before plugging it into the wall (or otherwise providing 120-VAC). Put in the fuse or switch on the cricuit breaker. Only then provide 120-VAC to the AIMS, and monitor your Voltage (at the BMS Bluetooth device, or your Coulomb Counter, or your battery terminals).
 
Did you use resistor (47 Ohms 10W should be fine) to precharge the capacitors bank in the AIMS Inverter charger to limit the inrush current first before directly connecting the cables? The BMS may have been tripped due to over current condition, you can try resetting the BMS.

Man, so much to learn here. Let's see.

I didn't precharge the capacitors in the AIMS charger, so i'll get some resistors for future use. Is that primarily for the large AH battery banks or would that apply to any lead acid 12V battery too? I'll start researching how to reset the Daly BMS too.
 
This appears to be a common-port Daly BMS. Do not connect the AIMS directly to the Battery "-" terminal! After eliminating any Voltage differential between the "B-" and "P-" wires of the BMS, using DVM set to measure OHMS (and not volts, and not shorting it out!) you should connect the charger "-" battery output terminal to the "P- terminal (on a grounding bus bar, along with loads and maybe going through a coulomb-counter meter before reaching "P-").

I have no idea what the DP switch settings are on the AIMS. My advice is to be sure that the BMS is functional (via bluetooth or UART), and then connect the negative leads properly. (Including "P-", after settling the voltage against B- by using the DVM reading "ohms".) THEN connect your "main" battery "+12V power lug into the charge and load bus (through a fuse block not yet connected, or circuit breaker not yet activated).

If your BMS needs to be reset, do that now.

Connect your AIMS charger to the "12V" bus and set your DP switches before plugging it into the wall (or otherwise providing 120-VAC). Put in the fuse or switch on the cricuit breaker. Only then provide 120-VAC to the AIMS, and monitor your Voltage (at the BMS Bluetooth device, or your Coulomb Counter, or your battery terminals).
Thanks for the quick replies!

1. Ok, I won't connect the charger directly to the batter, bypassing the BMS.
2. Regarding the voltage differential, i'm just checking the voltage at the battery terminals and the voltage at the battery positive terminal and the P- terminal on the BMS, correct? I assume the voltage likely won't be an exact match due to the resistance through the BMS, so 1 or 2 millivolts difference.
3. When I check the resistance between B- and P-, I am just looking for continuity and a value of 0, correct? If there's continuity, the board/fuse is still intact.
3. I ordered a cheap battery tester/monitor with a 200A shunt, so I'll connect that in line with the charger negative cable and the BMS P-.
4. The Daly unit that I have isn't a smart device, so I'll have to research options for resetting and confirming operation.
5. I should receive a Blue Seas 200A circuit breaker this week, so i'll add that to the positive cable.
6. After all devices wired, connect negative side of charger, then positive side and finally plug in 120VAC.

It looks like I have some homework to do, but please let me know if anything above sounds incorrect.
 
Man, so much to learn here. Let's see.

I didn't precharge the capacitors in the AIMS charger, so i'll get some resistors for future use. Is that primarily for the large AH battery banks or would that apply to any lead acid 12V battery too? I'll start researching how to reset the Daly BMS too.
Any time you connect the inverter or any electronics device with large bank of capacitors to any power source, you should charge up the caps of the inverter/device first, otherwise you will see big sparks, lead acid does not have BMS so there is nothing to shutdown.
 
I'm a bit confused- is this AIMS device a power Converter (i.e. a charger from 120-VAC into the Daly-equipped battery), or an Inverter (battery into 120-VAC loads), or a dual unit? If it's only a Converter-Charger, then the on-board capacitors should be charged from the AC side. If it's an Inverter, then it will have some "in-rush" (from 12-VDC) to charge capacitors - and AC loads should not even be attached until that after that has been completed.

From the picture, I only saw Converter functionality - 120-VAC to charge batteries of either "12 Volts" or "24 Volts".
 
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Thanks for the quick replies!

1. Ok, I won't connect the charger directly to the batter, bypassing the BMS.
2. Regarding the voltage differential, i'm just checking the voltage at the battery terminals and the voltage at the battery positive terminal and the P- terminal on the BMS, correct? I assume the voltage likely won't be an exact match due to the resistance through the BMS, so 1 or 2 millivolts difference.
3. When I check the resistance between B- and P-, I am just looking for continuity and a value of 0, correct? If there's continuity, the board/fuse is still intact.
3. I ordered a cheap battery tester/monitor with a 200A shunt, so I'll connect that in line with the charger negative cable and the BMS P-.
4. The Daly unit that I have isn't a smart device, so I'll have to research options for resetting and confirming operation.
5. I should receive a Blue Seas 200A circuit breaker this week, so i'll add that to the positive cable.
6. After all devices wired, connect negative side of charger, then positive side and finally plug in 120VAC.

It looks like I have some homework to do, but please let me know if anything above sounds incorrect.
2. You might, before attaching the "B-" lead, connect your battery "-" momentarily to your DC grounding bus directly (and not through the Daly), just to assure that the battery "-" is not "floating" above or below the potential of your DC system grounding bus.

3. With "P-" still disconnected, the resistance versus "B-" should settle to nearly zero. IF IT DOES NOT, then your Daly has been tripped and disabled from excess current - and it will need to be reset, using the 2-pin reset method. (Before connecting "P-").

3A. A battery monitor shunt of only 200A burns out the monitor when the current reaches and exceeds 200A. Can you modify your order to obtain a bigger shunt? (if the circuit breaker #5 allows for 200A, then the shunt "maximum current" size should be in the range of 350A to 500A.)
 
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I'm a bit confused- is this AIMS device a power Converter (i.e. a charger from 120-VAC into the Daly-equipped battery), or an Inverter (battery into 120-VAC loads), or a dual unit? If it's only a Converter-Charger, then the on-board capacitors should be charged from the AC side. If it's an Inverter, then it will have some "in-rush" (from 12-VDC) to charge capacitors - and AC loads should not even be attached until that after that has been completed.

From the picture, I only saw Converter functionality - 120-VAC to charge batteries of either "12 Volts" or "24 Volts".
Yes, it's a 120VAC power converter charger. That makes sense about the AC charging the capacitors.

AIMS Power CON120AC1224DC AC Converter & Battery 12V or 24V Smart Charger 75 amps Listed to UL 458 & CSA​

 
2. You might, before attaching the "B-" lead, connect your battery "-" momentarily to your DC grounding bus directly (and not through the Daly), just to assure that the battery "-" is not "floating" above or below the potential of your DC system grounding bus.

3. With "P-" still disconnected, the resistance versus "B-" should settle to nearly zero. IF IT DOES NOT, then your Daly has been tripped and disabled from excess current - and it will need to be reset, using the 2-pin reset method. (Before connecting "P-").

3A. A battery monitor shunt of only 200A burns out the monitor when the current reaches and exceeds 200A. Can you modify your order to obtain a bigger shunt? (if the circuit breaker #5 allows for 200A, then the shunt "maximum current" size should be in the range of 350A to 500A.)
Thanks for all the advice.

I didn't realize that my shunt should be larger...i might have to return and order a larger one. I'll do that now.
 
I'm a bit confused- is this AIMS device a power Converter (i.e. a charger from 120-VAC into the Daly-equipped battery), or an Inverter (battery into 120-VAC loads), or a dual unit? If it's only a Converter-Charger, then the on-board capacitors should be charged from the AC side. If it's an Inverter, then it will have some "in-rush" (from 12-VDC) to charge capacitors - and AC loads should not even be attached until that after that has been completed.

From the picture, I only saw Converter functionality - 120-VAC to charge batteries of either "12 Volts" or "24 Volts".
OP post #1: "I connected the battery cables to charger prior to plugging it in, then turned it on, but the red fault light is on. It remains on after unplugging the charger as well."
He made the connection to the charger before plugging the charger in to the AC outlet.

OP charger:
 
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