A&D EK-15KL Manual, Explained: Keys, Counting, Calibration, Function Settings and RS-232C

By MNM Scales · Last updated October 31, 2026

The A&D EK-15KL is a 15 kg by 0.1 g bench scale with a 300 x 210 mm pan, a backlit display and an RS-232C port built in. Its manual covers two scales: the single-range EK-15KL at 1/150,000 resolution and the dual-range EK-30KL (3 kg x 0.1 g and 30 kg x 1 g). This guide keeps only what applies to the EK-15KL, with the display codes as they appear on the scale and the factory settings marked.

EK-15KL specifications from the manual

Item	EK-15KL
Capacity x readability	15 kg x 0.1 g (15,000 g, 1/150,000)
Repeatability (standard deviation)	0.3 g
Linearity	±0.6 g
Sensitivity drift	±20 ppm per °C (10 to 30 °C)
Calibration weight (factory setting)	15 kg (not included); the value can be changed
Counting	Samples of 5, 10, 25, 50 or 100 pieces; up to 150,000 pieces; minimum unit mass 0.1 g
Percent mode	Displays to 0.1 percent
Other units (capacity x readability)	oz 529.110 x 0.005 · lb 33.0690 x 0.0005 · ozt 482.260 x 0.005
Display	7-segment LCD with backlight, 22 mm characters, updates about 10 times per second
Power	AC adapter (included), or a sealed lead-acid battery (not included) for about 100 hours with the backlight off
Pan and weight	300 x 210 mm pan; scale about 4.2 kg

Setting up the EK-15KL

1. Unpack it. The box holds the main unit, the AC adapter and the instruction manual. Check that the adapter suits your outlet.
2. Choose the spot. A solid, level surface away from dust, drafts, vibration, large temperature swings, condensation, magnetic fields, direct sun, heaters and air conditioners.
3. Level it. Turn the leveling feet until the bubble in the spirit level sits in the center of the circle.
4. Power it. Plug the AC adapter into the jack under the display. A&D recommends leaving it connected whenever possible; staying plugged in does the scale no harm.
5. Warm it up for at least 30 minutes before use.
6. Calibrate when you first set it up and every time you move it (see below).

If static seems to upset the reading, ground the scale through the grounding terminal on the back. The security slot takes a lock cable (not included).

At power-on the EK-15KL shows every symbol, then zero with the ZERO indicator once the reading is steady (power-on zero, within ±10 percent of capacity). If something heavier is on the pan, the scale tares it and shows NET and ZERO.

The keys and the CAL switch

Key	In weighing	In the function settings
ON/OFF	Turns the scale on (with power-on zero) or off	Cancels and turns the scale off
MODE	Steps through the stored units, pcs and percent; hold it in pcs or percent to store a new sample	Selects a class or item; moves to the next digit
PRINT	Sends the stable reading to a printer or PC; hold it for GLP title and end blocks	Opens the selected class; stores the settings
RE-ZERO	Zeroes the display, or tares a container	Changes the parameter or the blinking digit
CAL switch	Under the calibration switch cover (remove the screws); hold it to start calibration	Switches the sign (+/-) of comparator limits

RE-ZERO zeroes the display within ±2 percent of capacity from the power-on zero point. Above that it subtracts the load as tare and turns on NET, so one key handles both jobs. Wait for the STABLE indicator before reading or printing.

Units, counting and percent

MODE steps through g, kg, pcs, percent, oz, lb and ozt, skipping any unit not stored. To keep only the units you use, open the function settings, press MODE until Unit shows, press PRINT, then for each unit press MODE to reach it and RE-ZERO to select it (STABLE turns on). Press PRINT to store. The first unit selected is the one the scale starts in.

Counting pieces

1. Press MODE until pcs shows, then press and hold MODE to store a new sample.
2. Press PRINT to choose 5, 10, 25, 50 or 100 samples.
3. Place an empty container and press RE-ZERO; the right side shows zero.
4. Add the number of samples shown and press MODE to store the unit mass, then remove the samples and count.

lo means a piece is too light to store. If the sample is light enough that counting error could grow, the scale blinks a larger sample size; add that many pieces and press MODE. ACAI (Automatic Counting Accuracy Improvement) then refines the unit mass: add a few more pieces, about as many as shown, and leave the pan alone while the ACAI indicator blinks.

Percent mode

Press MODE until percent shows and hold MODE. Press RE-ZERO to show 100.0 percent, place the reference sample and press MODE to store it. Anything placed afterwards reads as a percentage of that reference.

HI/OK/LO comparator

The comparator lights HI, OK or LO against an upper and lower limit. One pair of limits serves grams, counting and percent: 001010 reads as 101.0 g, 1,010 pcs or 101.0 percent.

1. With the power off, hold RE-ZERO and press ON/OFF. func appears.
2. Press PRINT, then MODE until Cp shows, and RE-ZERO to choose the mode (0 off, 1 all data, 2 stable data, 3 plus data away from zero, 4 stable plus data away from zero, 5 all data away from zero, 6 stable data away from zero). Press PRINT to store.
3. At Cp Hi press PRINT and enter the upper limit: MODE picks the digit, RE-ZERO changes it, the CAL switch flips the sign, PRINT stores.
4. Enter the lower limit the same way at Cp lo, then press RE-ZERO to return to weighing.

“Away from zero” means outside ±4 digits of zero in grams or kilograms, so an empty pan does not light LO.

EK-15KL function settings

Enter the function table with the power off: hold RE-ZERO and press ON/OFF. MODE moves between items, RE-ZERO changes the value and PRINT stores the class; ON/OFF cancels. The first column is the code on the display.

Code	Setting	Values (factory setting in bold)
poff	Auto power-off (after about 5 minutes at zero)	0 off, 1 on
Hold	Display lock (holds a reading so it is easier to read)	0 off; 1 on, released by a change over ±10 digits; 2 ±50; 3 ±100; 4 ±200 digits
trc	Zero tracking	0 off, 1 on
pnt	Decimal point	0 dot, 1 comma
Cp	Comparator mode	0 off, 1 to 6 (see above)
prt	Data output mode	0 stream; 1 key; 2 key plus auto-print A; 3 key plus auto-print B; 4 command only
bps	Baud rate	0 = 2400, 1 = 4800, 2 = 9600, 3 = 1200 bps
btpr	Data bits and parity	0 = 7 bits even, 1 = 7 bits odd, 2 = 8 bits none
pUse	Pause between continuous data	0 none, 1 = 1.6 s (AD-8121 printer)
info	GLP output	0 none, 1 AD-8121 format, 2 general format
aCai	ACAI	0 off, 1 on
Umin	Minimum unit mass for counting	0 = 1 digit, 1 = 1/10 digit, 2 = total sample of 5 digits or more
smpl	First sample size offered	0 = 10, 1 = 25, 2 = 50, 3 = 100, 4 = 5 pcs
ltUp	Backlight	0 always off; off 1 = 5, 2 = 10, 3 = 30, 4 = 60 seconds after STABLE; 5 always on
Unit / id	Stored units / GLP ID number	See the units and GLP sections

A&D’s own example: to turn auto power-off on and ACAI off, enter func, press PRINT (poff 0), RE-ZERO (poff 1), MODE until aCai 1, RE-ZERO (aCai 0), then PRINT to store.

How to calibrate the EK-15KL

Calibrate when you first use the scale, after moving it, when the room changes and on a regular schedule. Use a weight of more than two thirds of capacity, so at least 10 kg; the factory value is 15 kg. A&D specifies OIML class F1; see our calibration weight classes guide, and shop calibration weights (not included). No weight is needed for a zero calibration alone.

1. Turn the scale on and warm it up for at least 30 minutes with nothing on the pan.
2. Loosen the screws on the calibration switch cover. Press and hold the CAL switch until Cal appears, then release. Cal 0 shows.
3. To change the weight value, press PRINT; the stored value shows in grams. MODE picks the digit, RE-ZERO sets it and PRINT stores it.
4. With the pan empty, press RE-ZERO to calibrate zero. Do not touch the pan. The weight value then appears. (To stop after a zero calibration, press ON/OFF or the CAL switch.)
5. Place a weight matching the displayed value and press RE-ZERO.
6. end appears. Remove the weight and press RE-ZERO to return to weighing, or ON/OFF to turn off. With GLP output on, glp shows while the calibration report prints.

The value you store stays in memory after power-off. If you move the scale and have no weight on hand, A&D’s gravity acceleration correction compensates: at Cal 0 press MODE, set the local value from the gravity map at the back of the manual (MODE picks the digit, RE-ZERO sets it) and press PRINT. A calibration with a weight on site makes it unnecessary.

CAL E means the weight was too heavy for the stored value and -CAL E too light; check the pan and the weight value. If the reading drifts after calibration, see scale will not zero or keeps drifting.

RS-232C, printing and GLP

The RS-232C port is standard. The scale is DCE and connects to a PC or printer with a straight 9-pin D-Sub cable: pin 2 transmit, pin 3 receive, pin 5 ground, 6 DSR, 7 RTS, 8 CTS. Out of the box it sends on a PRINT press (prt 1) at 2400 bps, 7 data bits, even parity. Set prt 0 for continuous data, 2 or 3 for auto-print when a stable load lands, or 4 for commands only.

From a PC the scale answers Q (send the reading), Z (same as RE-ZERO) and U (same as MODE). Lines start with ST (stable), QT (stable count), US (unstable) or OL (over range), carry the value and unit, and end in CR LF. A&D offers its WinCT software free for logging into a PC. For cables and adapters, see how to connect a scale to a computer.

For GLP records, set an ID number under id and choose info 1 with pUse 1 for an AD-8121 printer (printer in MODE 3) or info 2 with pUse 0 for a PC. Hold MODE and PRINT until CC shows to run a calibration test that checks accuracy without changing the calibration; hold PRINT until start or recend to add a title or end block around a series of weights.

Battery power

The EK-15KL can run on a 6 V, 4.0 Ah sealed lead-acid battery, which A&D lists as option OP-02; we sell the HC-02i rechargeable battery for the EK-15KL and EK-30KL (not included). Remove the adapter, unscrew the battery cover underneath, connect red to + and black to -, refit the cover and switch on. A full charge runs about 100 hours with the backlight off.

Plug the adapter back in to recharge; a full charge takes about 15 hours, between 0 and 40 °C. Charge a new battery fully before use, and recharge at least every three to six months even in storage. Lb on the display means the battery is depleted.

EK-15KL error codes

Display	Meaning	What to do
E	Overload	Remove the load; it is above 15 kg
Error 5	Excessive load detected	Remove everything and check that the pan is seated correctly
-E	Underload: strong upward force	Check for anything caught under the edge of the pan
Lo	Piece or 100 percent reference too light	Use more pieces or a heavier reference
Blinking 10, 25, 50 or 100	Sample too light for accurate counting	Add the number of pieces shown and press MODE
CAL E / -CAL E	Calibration weight too heavy / too light	Check the pan and the calibration value
Lb	Battery depleted	Recharge it or run on the AC adapter
Hb	AC adapter voltage too high	Check the adapter matches your outlet
Error 1	Reading will not settle	Stop vibration and drafts, then press MODE
Error 2, 3, 4 or 6	Internal error	Clear the pan and turn the power off and on; if it stays, it needs service

Load cells can fail after a shock load, and a damaged adapter stops power. If an error will not clear, our repair bench can help; codes for other brands are in our scale error codes guide.

Selling by weight

The EK-15KL is not NTEP. It is built for production, counting, kitting, lab and shop weighing, where its 0.1 g readability across 15 kg pays off. For selling general goods by weight, A&D makes the EK-15KLN, NTEP Class III. For buying or selling precious metals by weight, choose a Class II model such as the A&D EK-1200i (1,200 g x 0.1 g) or the A&D FX-200iN. Our legal for trade jewelry scale guide and EK-1200i vs EK-610i explain the Class II options.

Texas note: TDA does not require an NTEP certificate for every device, but the scale must meet NIST Handbook 44 and suit its use; some scales do need one, so we recommend NTEP models and can check yours. See TDA’s scales used in trade guidance (PDF) and our TDA scale certification guide, or call us or TDA to confirm your use.

Not sure your use counts as trade? Try our free legal-for-trade scale checker.

Care and storage

Clean with a lint-free cloth lightly dampened with mild detergent; no organic solvents. Ship it in the original packing. Keep sharp tools such as pencils off the keys and keep the pan free of dust and liquid. The EK-30KL (3 kg x 0.1 g and 30 kg x 1 g) uses this same manual, and the EK-30KLN is its NTEP version; see all A&D bench scales.

Calibration, repair and rentals

• Calibrated before it ships: in-house calibration $250 or NIST calibration certificate $595 for scales from 6.2 to 35 kg, including the EK-15KL. See NIST vs in-house certificates.
• Mail-in calibration: pack the scale in its original packing, as A&D recommends, and ship it to our shop with the mail-in calibration service.
• Cypress pickup by appointment: drop off or pick up at our Cypress, TX shop (21249 FM 529 Rd, Cypress, TX 77433).
• On-site service: on-site calibration is $295 plus $2 per mile per visit, plus the calibration fee for each scale. Our TDA-registered technicians handle bench scales and balances across the Houston area.
• Repair: load cell, adapter, battery and keypad problems go to our scale repair bench.
• Rentals: we rent all types of scales; ask about a scale rental while yours is in for service.

Frequently asked questions

Where can I find the A&D EK-15KL manual?

A&D publishes the EK-L series instruction manual (1WMPD4002971), which covers the EK-15KL and EK-30KL, as a PDF, and the specifications on its EK-L series page.

How do I calibrate the A&D EK-15KL?

Warm it up for 30 minutes, open the calibration switch cover and hold the CAL switch until Cal shows. With the pan empty press RE-ZERO, place the 15 kg weight (or the value you set) and press RE-ZERO again. When end shows, remove the weight.

What calibration weight does the EK-15KL use?

The factory value is 15 kg. A&D asks for a weight above two thirds of capacity, so at least 10 kg, in OIML class F1. You change the stored value by pressing PRINT at Cal 0. Weights are not included.

How do I open the function settings on the EK-15KL?

With the power off, hold RE-ZERO and press ON/OFF until func appears. MODE moves between items, RE-ZERO changes the value, PRINT stores and ON/OFF cancels.

Can the EK-15KL connect to a computer?

Yes. RS-232C is standard: a straight 9-pin cable to a PC or printer, factory set to 2400 bps, 7 bits, even parity, sending on a PRINT press. It also accepts the Q, Z and U commands.

What does Lo mean on an A&D EK-15KL?

The piece or reference is too light to store in counting or percent mode. Use more pieces or a heavier reference.

Does the EK-15KL run on a battery?

Yes, on a 6 V sealed lead-acid battery for about 100 hours with the backlight off; it recharges in about 15 hours through the AC adapter. The battery is not included.

Is the EK-15KL legal for trade?

The EK-15KL is not NTEP; the EK-15KLN is the NTEP Class III version. For buying or selling precious metals by weight, choose a Class II model such as the A&D EK-1200i or FX-200iN.