I'm currently running a PD4560 60-amp converter/charger in my fifth wheel, but I'm planning to upgrade to lithium batteries and want to make sure I get the right setup. My existing Progressive Dynamics unit obviously isn't designed for LiFePO4 batteries - I can use boost mode to charge them up, but I know that's not ideal for battery longevity.
I just purchased a 30 amp generator and I'm wondering if it will have enough capacity to handle not just my current charger, but potentially a larger lithium-compatible unit. I'm considering upgrading to a 75 or even 90 amp charger to reduce charging times, but I need to make sure my generator can handle the load. I'm trying to figure out the actual AC amp draw of these higher-capacity chargers and whether my 30 amp generator will be sufficient.
What are the best lithium-compatible converter/charger options that would work with my generator setup, and how do I properly size the charger capacity to match my lithium battery bank?
Your 30 amp generator will power any RV converter charger. For lithium, get charger with proper LiFePO4 profile. Progressive Dynamics, IOTA with IQ-Lifepo4, or Victron all work well. Match amp rating to battery bank capacity.
Your PD4560 converter pulls approximately 8.5 amps at full 60-amp charging output, so your new generator should handle it fine through the 30-amp shore power connection. However, upgrading to a 75 or 90-amp lithium-compatible charger will pull proportionally more power - around 12-15 amps for a 75-amp unit and 15-18 amps for a 90-amp charger. Since you're already using boost mode successfully with your current setup, the generator upgrade path makes sense, but you'll want to verify your generator's continuous output rating and ensure your 30-amp shore power wiring can handle the increased load of a larger charger.
The main issue you're facing is that your PD4560 uses the older lead-acid charging profile, which isn't optimized for lithium batteries even in boost mode. Progressive Dynamics converters from that era typically charge at 13.6V in normal mode and 14.4V in boost mode, while lithium batteries prefer a more precise 14.2-14.8V charging voltage with different absorption and float characteristics.
Generator sizing confusion often stems from not understanding that converter amp ratings refer to DC output, not AC input draw. Your 60-amp converter doesn't pull 60 amps from the 120V AC side - it pulls much less due to the voltage conversion ratio. The actual AC draw depends on DC load, battery state of charge, and converter efficiency (typically 85-90% for modern units).
Many RVers also underestimate the importance of proper wire sizing when upgrading to higher-amperage chargers. Your existing 30-amp shore power connection may become a bottleneck if you jump to a 90-amp charger, especially when combined with other AC loads like air conditioning or microwaves running simultaneously.
Before making any upgrades, verify your generator's grounding and bonding compatibility with your RV electrical system, then test your new generator with the existing PD4560 to establish a baseline. Connect the generator to your 30-amp shore power inlet and monitor the charging performance with your batteries at various states of charge. Use a clamp meter to measure the actual AC current draw at the generator output - this will give you real-world data for your specific setup.
Research lithium-compatible converters in the 75-90 amp range. Popular options include the Progressive Dynamics PD9175LI (75-amp) or PD9190LI (90-amp), WFCO WF-9000 series, or standalone chargers like Victron or Renogy units. Check the specifications for AC input current requirements - most quality 75-amp lithium chargers pull 12-15 amps AC, while 90-amp units typically draw 15-20 amps (efficiency can drop to 75-80% at full load).
Verify your generator's continuous power rating and surge capacity. A quality 3000-watt generator should easily handle a 75-amp charger plus moderate additional loads, while a 90-amp charger might push smaller generators near their limits when combined with other appliances.
Examine your existing DC wiring from the converter to your battery bank. Higher amperage chargers require properly sized conductors - 75-90 amp charging typically needs 4 AWG or larger DC wiring depending on run length. Also check that your DC fuses/breakers and battery disconnect switches are rated for the increased current.
Start by documenting your current setup with photos and measurements. Note the existing DC wire gauge, fusing, and routing from your PD4560 to the batteries. Measure the physical dimensions of the converter compartment to ensure your chosen replacement will fit - some 90-amp units are significantly larger than the compact PD4560.
If upgrading the converter, turn off all power sources including shore power, generator, and battery disconnect. Wait several minutes for internal capacitors to discharge before touching any DC connections. Remove the old PD4560 by disconnecting the AC input wires (typically black hot, white neutral, green ground) and the DC output cables. Progressive Dynamics units typically have hardwired DC connections secured with terminal blocks.
Install the new lithium-compatible converter following the manufacturer's wiring diagram. Pay special attention to the DC output connections - ensure positive and negative cables are properly sized and securely terminated. Many lithium chargers include temperature sensing capabilities, so route the temperature sensor wire to your battery compartment as specified.
For the AC input side, verify that your existing 30-amp shore power wiring can handle the increased load. If installing a 90-amp charger, consider adding a dedicated AC branch circuit if your electrical panel has capacity, or ensure other high-draw appliances won't overload the system when charging at full rate.
Configure the new charger for your specific lithium battery type using the manufacturer's programming instructions. Most modern units offer multiple lithium profiles (LiFePO4, standard lithium, etc.) and allow voltage adjustments for optimal charging. Test the installation by monitoring charge rates and battery voltages during various charging scenarios.
Call a qualified RV electrician if you're uncomfortable working with 120V AC wiring or if your electrical panel modifications are needed for a higher-amperage installation. AC electrical work in RVs involves specific safety considerations and code requirements that vary by jurisdiction.
Seek professional help if your battery bank configuration is complex or if you're unsure about proper DC fusing and wire sizing for the upgraded amperage. Lithium battery systems often require specific Battery Management System (BMS) integration that affects charger selection and wiring.
Consider professional consultation if your generator and electrical system upgrades involve significant modifications to your 5th wheel's original design. Some installations may affect warranty coverage or require permits depending on local regulations and the extent of the electrical changes.
Get expert assistance if you experience any electrical issues during testing, such as tripped breakers, unusual heating, or inconsistent charging performance. These symptoms could indicate compatibility issues between your generator, charger, and battery system that require professional diagnosis.
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