SkyRC MC3000 vs XTAR VC4SL

Choose the SkyRC MC3000 when you want a rechargeable battery tester with adjustable discharge current, cutoff voltage and rest periods for controlled capacity comparisons. Choose the XTAR VC4SL for simpler automatic grading of supported Li-ion and NiMH cells, especially protected 21700 batteries, which SkyRC explicitly excludes. For sorting disposable household batteries, start with our household battery tester guide.

Quick picks: control the test or simplify the routine

Compare specifications and all conditions

Repeat capacity comparisons with recorded settings

Our pick

SkyRC MC3000

Deciding feature

Adjustable discharge current, cutoff, rests and saved programs

Main limitation

Requires choosing the correct chemistry and program

Automatic grading; protected 21700 cells

Our pick

XTAR VC4SL

Deciding feature

Automatic charge-discharge-charge capacity routine

Main limitation

Charging-current selection does not document adjustable discharge conditions

Full comparison table ↔

Swipe to compare. Row labels stay visible.

Your priority	Our pick	Deciding feature	Main limitation
Repeat capacity comparisons with recorded settings	SkyRC MC3000	Adjustable discharge current, cutoff, rests and saved programs	Requires choosing the correct chemistry and program
Automatic grading; protected 21700 cells	XTAR VC4SL	Automatic charge-discharge-charge capacity routine	Charging-current selection does not document adjustable discharge conditions

Your priority	Our pick	Deciding feature	Main limitation
Repeat capacity comparisons with recorded settings	SkyRC MC3000	Adjustable discharge current, cutoff, rests and saved programs	Requires choosing the correct chemistry and program
Automatic grading; protected 21700 cells	XTAR VC4SL	Automatic charge-discharge-charge capacity routine	Charging-current selection does not document adjustable discharge conditions

The question is which test you need to control, rather than which screen has more digits.

MC3000 vs VC4SL: the specifications that change the choice

Sources: SkyRC product specifications, its text manual, XTAR's model comparison and capacity explanation. These are manufacturer specifications, not results from a shared test bench.

Best for controlled comparisons: SkyRC MC3000

The MC3000, model SK-100083, earns its recommendation through control over the discharge routine. Its manual documents 0.01 A increments in Advanced mode, an under-load CUT VOLT setting and separate charge/discharge rest periods. Save the intended settings as a program so subsequent cells use the same routine.

Use Refresh to compare the discharge capacities of initially charged cells; use Discharge when you deliberately want to measure the charge remaining at insertion. Cycle repeats charge/discharge patterns. Break-in is restricted to NiMH/NiCd/Eneloop, and Storage is for supported lithium chemistries. Neither program name promises that an old cell will recover its original capacity.

The discharge ceiling needs its footnote. SkyRC permits four nickel-based cells at 2 A per slot, or four lithium-based cells at 1 A per slot. To maintain more than 1 A on a lithium cell, the manual requires that no other slot be busy. That restriction matters when planning a batch; the maximum setting is not available independently on every lithium slot.

SkyRC documents an aluminum cooler and fan. Its manual warns that heat at extreme discharge loads can affect accuracy. Allow ventilation and record temperature conditions instead of assuming a higher current always makes a better comparison.

See MC3000 specifications and downloads at SkyRC

Best for simpler grading: XTAR VC4SL

The VC4SL is our starting choice when you want to run a capacity-grading routine without configuring the MC3000's detailed discharge parameters. XTAR describes the sequence as charging, measuring capacity during discharge, then charging again. Its storage function adjusts battery voltage for storage; that is a different task from capacity grading.

The current product page lists manual charging-current selection from 0.25 A to 3 A. XTAR's buying guide specifies 3 A × 1, 2 A × 2 and 1 A × 4, with lower selections available. Those are charging figures: they do not establish the grading load, discharge cutoff or how long a complete grading cycle takes.

XTAR's capacity article discusses slot-to-slot shunt differences and heat effects. For repeat screening, our advice is to keep the slot and conditions consistent and investigate an unexpected result before discarding a cell. We cannot name an accuracy winner from these documents.

See VC4SL specifications and manual at XTAR

Chemistry and cell sizes: match both

A storage footnote is not a charging specification. XTAR's buying guide adds 3.2 V LiFePO4 “In store mode” to VC4SL, while its product page lists Li-ion and NiMH. Do not extend that footnote to LiFePO4 charging or grading. Likewise, SkyRC's RAM label means rechargeable alkaline, not permission to charge ordinary alkaline batteries.

For unusual sizes, these are the manufacturers' explicit lists, not continuous ranges:

• MC3000: AAAA, AAA, AA, Sub-C, C and D; 10340, 10350, 10440, 10500, 12340, 12500, 12650, 13450, 13500, 13650, 14350, 14430, 14500, 14650, 16340, RCR123, 16500, 16650, 17350, 17500, 17650, 17670, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22500, 22650, 25500, 26500, 26650, 26700, 32600, 32650 and 32700. The manual limits D, 32600, 32650 and 32700 to two cells alongside two other batteries; the protected-21700 exclusion still applies.
• VC4SL: XTAR's current comparison lists AAA, AA, A, SC and C; 10440, 14500, 14650, 16340, 17335, 17500, 17670, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22650, 25500, 26650 and 32650. For NiCd, AAAA or D cells, obtain model-specific confirmation rather than extending this list.

• Yes: NiMH AA/AAA: within the documented scope of both recommendations
• Partly: Unusual chemistry or size: match the exact cell to the maker's list
• No: Protected 21700: excluded by SkyRC for MC3000
• No: Regulated lithium AA/AAA: absent from these product-page chemistry lists

Capacity results: make the conditions comparable

Read discharge capacity. XTAR explains why charging input and delivered discharge capacity differ. A normal charge display should not be substituted for a completed grading result.

Record the endpoint as well as current. SkyRC's CUT VOLT is measured under load. Its D.REDUCE option continues discharge at reduced current after reaching that voltage, extracting additional charge. Record that setting too; identical cutoff labels alone do not establish identical routines.

Compare like with like. XTAR identifies discharge rate and temperature as capacity influences. SkyRC recommends using fixed charge/discharge rates for comparisons. Match the cell maker's conditions when assessing a label claim; use the same documented routine when comparing your own cells over time. A result from one charger's program is not automatically interchangeable with a result from the other.

1. 1

   Identify the cell

   Record its chemistry and exact size before selecting a program.

2. 2

   Record the routine

   Note charge and discharge settings, endpoint, rest periods and slot where available.

3. 3

   Record the result

   Use completed discharge capacity and note temperature conditions before comparing cells.

Buying guide: variants, power and a complete gift

Resolve the XTAR suffix. XTAR calls VC4 PLUS the retail version of VC4SL, with the same features, functions and looks. Its family comparison says VC4, VC4L and VC4H lack capacity testing. VC4S has capacity testing but lacks protected-21700 support. VX4 is a separate chemistry choice; its support for rechargeable 1.5 V lithium cells does not transfer to VC4SL.

MC3000 package and updates: SkyRC lists the charger, AC switching adapter, AC power cord and manual. Confirm the US wall plug. The product page now lists an English V1.30 manual and V1.27 firmware downloads; do not treat the older V1.17 text manual linked above as the latest release. The detailed discharge controls cited here were also checked against the current manual's rendered pages.

SkyRC's input wording differs: its product page says 11–18 V/4 A, while the manual specification table says 12–18 V/60 W. Use the supplied adapter; ask SkyRC for a matching replacement rather than choosing by one of those figures alone.

VC4SL power: XTAR specifies QC3.0, 5 V/3 A or 9 V/2 A, through USB-C. Its product page also recommends named PD adapters, but its protocol table identifies VC4SL as QC3.0. A clear option to check is XTAR's QC3.0 adapter, offered with a US plug; match its output and the cable to the charger. The cited product page does not establish whether the adapter or cable accompanies a particular US package. Confirm both before ordering.

For a gift, get the recipient's cell labels and existing charger model first. Prefer MC3000 when controlled routines fill a missing capability; prefer VC4SL when automatic grading and protected-cell fit solve the need. Confirm the complete power path and whether the recipient wants another charger before buying. Our gifts for electrical engineers guide covers the wider choice.

How we choose

We compared official product pages, model tables and manuals, including the current manuals' rendered pages where PDF text extraction failed. Detailed SkyRC citations retain the readable older manual alongside its current downloads. We separated confirmed specifications from package details and grading parameters that the available text sources do not establish. We have not physically evaluated either charger. See how we choose and how we measure.

Verdict

Buy MC3000 for control over the discharge routine; buy VC4SL for automatic grading and documented protected-21700 support. Choose a supported pulse-load household tester when you want a brief screening indication: ZTS describes that method separately from these discharge routines. For vehicle batteries, use our car battery tester guide. Keep an existing charger if it already answers your question; buy the missing measurement capability.