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JK BMS 5A Parallel Module for JK BMS | Safe Battery Paralleling | LiFePO4 Oz - JK-BLMK-5A
JK-BLMK-5A Parallel Module (5A Current Limiter) for JK BMS
If you’re paralleling multiple JK BMS battery packs, this is the little module that prevents the big mistake: surge (inrush) current when you connect packs together.
What it does: Limits equalisation / inrush current between packs to ~5A so you can parallel safely.
Quick Benefits
- Protects BMS + wiring from connection surges
- Makes parallel expansion controlled and safer
- Ideal for scalable off-grid battery banks
- Designed for JK BMS models with parallel support
Why You Need a Parallel Module
When you connect two lithium packs in parallel, even a tiny voltage difference can create a large equalisation current. That surge can stress cells, busbars, connectors, and in some cases damage electronics.
The JK-BLMK-5A slows that down by limiting the current to roughly 5A, so the packs equalise safely.
Compatibility (Read This)
Important: This module only works with JK BMS models that support parallel communication. If your BMS does not have parallel support, this module won’t magically make it parallel-capable.
Common compatible example:
- JK-B2A8S30P-HC (and other JK models with the parallel interface)
If you’re not sure which JK model you have, message us the model number (or a photo of the label) and we’ll tell you.
Technical Overview
Current limiting: ~5A
Use case: Parallel battery packs safely
Works with: JK BMS with parallel comms
Installation Notes (Do It Properly)
- Bring packs to similar voltage before connecting in parallel.
- Use correct cable sizing, busbars and protection devices.
- Follow JK app settings for parallel-enabled systems.
- This module helps manage inrush current — it doesn’t replace good electrical design.
If you want us to sanity-check your parallel plan, send through your setup (voltage, number of packs, inverter model). We’d rather you do it once and do it right.
Why Buy From LiFePO4 Oz?
- Australian family-owned
- We build real off-grid systems — not just sell parts
- Practical support from people who understand JK BMS setups
- Designed for DIY builders who want long-term reliability
FAQ
Can I parallel packs without this module?
Will this work with any JK BMS?
What should I do if I’m unsure about compatibility?
Note: Specs and compatibility depend on your JK BMS model and system design. If you're building a parallel bank, ensure correct protection, cable sizing and safe commissioning practices.
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We have a 30-day return policy if the item is damaged or is not as described, which means you have 30 days after receiving your item to request a return.
To be eligible for a return, your item must be in the same condition that you received it, unused, with tags, and in its original packaging. You’ll also need the receipt or proof of purchase.
To start a return, you can contact us at sales@lifepo4oz.com. If your return is accepted, we’ll provide instructions on how and where to send your package. Items sent back to us without first requesting a return will not be accepted.
You can always contact us for any return question at sales@lifepo4oz.com.
If you change your mind, you may be eligible for a return, however the items must be unused and in their original packaging. Once returned to us, we will inspect the goods and, if approved, a 20% restocking fee will apply.
Damages and issues
If you receive any items which appear to be damaged, do not attempt to use them. Please inspect your order upon receipt and contact us immediately if the item is defective, damaged, or if you receive the wrong item, so that we can evaluate the issue and make it right.
Products damaged in transit
If you receive a shipment that has been damaged in transit, a replacement or refund may be provided, subject to the following conditions:
- The return or damage claim must be made within 24 hours of receiving the shipment.
- All shipments must be inspected for damage during the unloading process.
- Clear photos of the damaged packaging and damaged product must be provided as evidence.
- Photos must be taken during the unloading process.
- Photos must clearly show all damage and, where possible, the likely cause of the damage.
- The total approved claim value, including freight costs, will be credited to your account.
Exceptions / non-returnable items
We do not accept returns for hazardous materials, flammable liquids, or gases. Please get in touch if you have questions or concerns about your specific item.
Exchanges
The fastest way to ensure you get what you want is to return the item you have, and once the return is accepted, make a separate purchase for the new item. A 20% restocking fee will apply.
Refunds
We will notify you once we’ve received and inspected your return, and let you know if the refund was approved or not. If approved, you’ll be automatically refunded to your original payment method. Please remember it can take some time for your bank or credit card company to process and post the refund.
All orders will be safely packed and shipped within 1 day. All products are shipped via Road Freight only.
All efforts are made to ensure the products safe during transport, however if you receive an item which looks like it may have been damaged during tranport you must take a photo before trying to use the product.
Shipping
All orders are shipped via Road Freight. As such there is not Express Shipping available.
RETURNS
We aim to keep our customers happy and if you are unhappy with your items due to them being damaged or not as described, simply return them for a refund. A 20% restocking fee will apply.
Top Quality Goods
Our aim is to provide high-quality products at an affordable price. If you receive a product that is damaged, do not use the item. Please inform us within 24 hours of receiving that product. We will replace the product as soon as possible without any charges.
REFUNDS
A refund will be provided if you have purchased an item that does not operate as described. Once we have verified you claims we will offer a refund and pay for the return freight cost.
