OHAUS RC31P15 Manual, Explained: Setup, Counting, Library and Calibration

This RC31P15 manual guide covers setup, parts counting, the 30-item library, error codes and calibration for the NTEP OHAUS Ranger Count 3000 RC31P15 (30 lb x 0.001 lb), on sale for $741.00 (regular $1,252.00), in stock.

The OHAUS RC31P15 is the 30 lb x 0.001 lb (15 kg x 0.5 g) model in the Ranger Count 3000 line, built for fast parts counting, kitting, inventory and checkweighing. This page follows the official OHAUS Ranger Count 3000 Series instruction manual (30037454), the U.S. Ranger Count 3000 datasheet and NTEP Certificate of Conformance 13-022A2. Choosing a counting scale first? Start with our counting scale buying guide or the small-parts counting scale guide. Comparing OHAUS lines? See OHAUS Valor vs Ranger vs Scout.

RC31P15 manual at a glance: specifications

Item	OHAUS RC31P15
OHAUS item / model	30031790 / RC31P15
Capacity x readability (d)	30 lb x 0.001 lb (15 kg x 0.5 g)
Certified readability (e)	0.01 lb (5 g / 0.005 kg)
Linearity / repeatability	±0.001 kg (±1 g)
Counting resolution	1:1,500,000 internal; 1:30,000 displayed; 1:3,000 approved
Min. recommended sample / APW	10 g (0.02 lb) sample; 0.05 g (0.0001 lb) APW
Platform	11.8 x 8.9 in (300 x 225 mm), 304 stainless steel
Display	3-window backlit LCD (weight, APW and count) plus 3 checkweighing LEDs
Modes	Weighing, parts counting with APW auto-optimization, checkweighing, checkcounting, accumulation
Memory	30-item library
Calibration	External span or linearity; 15 kg / 30 lb span mass (not included)
Interface	RS232 included; second RS232, USB, Ethernet or second-scale input optional
Power	100–240 VAC adapter (included) or internal rechargeable battery (included); 210 hours typical, 12-hour charge
Operating temperature	14 °F to 104 °F (−10 °C to 40 °C)
Dimensions / net weight	12.2 x 12.9 x 4.6 in (L x W x H); 9.2 lb (4.2 kg)
Approvals	NTEP Class III, CC 13-022A2 (nmax 3,000); Measurement Canada AM-5907C
In the box	Scale, sub-platform, stainless pan, power cord, instruction manual / CD, warranty card, capacity labels if they are not already applied

Ranger Count 3000 models in stock

The RC31P15 shares its chassis, 30-item library and menu with the rest of the Ranger Count 3000 line. Pick the capacity that fits the parts you count. Every model below is NTEP Class III under the same certificate, in stock, and priced at $741 (regular $1,252). Link and buy the keeper listing for the RC31P15.

Model	Capacity x d	Certified e	Price
RC31P1502	3 lb x 0.0001 lb (1.5 kg x 0.05 g)	0.001 lb / 0.5 g	$741
RC31P3	6 lb x 0.0002 lb (3 kg x 0.1 g)	0.002 lb / 1 g	$741
RC31P6	15 lb x 0.0005 lb (6 kg x 0.2 g)	0.005 lb / 2 g	$741
RC31P15 (this guide)	30 lb x 0.001 lb (15 kg x 0.5 g)	0.01 lb / 5 g	$741
RC31P30	60 lb x 0.002 lb (30 kg x 1 g)	0.02 lb / 10 g	$741

Setting up the RC31P15

1. Use the scale on a firm, steady surface, with enough space around it. Avoid drafts, vibration, heat sources and rapid temperature changes.
2. Press the sub-platform in until it locks, then set the stainless pan on top. The scale can be used without the pan if you need to.
3. Level it: turn the adjustable feet until the bubble sits in the center of the level indicator on the front of the scale. Re-level it whenever you move it.
4. Connect the included AC cord to the power input, then to a matching outlet. You can use the scale on AC power right away.
5. Charge the internal battery for 12 hours before running on battery power. The scale switches to battery automatically if AC power is lost, and it keeps charging whenever it is plugged in. Typical battery life is 210 hours with the backlight off. Charge it in a dry place at room temperature.
6. Press and hold On/Zero for one second to turn the scale on (it runs a self-test). Press and hold the same key until OFF appears to shut it down.

The battery is a sealed lead-acid pack. The manual requires replacement only by an authorized OHAUS dealer. When the battery icon blinks quickly, about 30 minutes of use remain; when lo.bat appears, the scale shuts off.

Controls, counting and the 30-item library

The RC31P15 has three backlit windows: weight, average piece weight (APW) and count, plus yellow/green/red checkweighing LEDs on the left. A 20-key pad (8 function keys and a numeric keypad) runs the scale. Short presses handle On/Zero, Print, Target, M+ (accumulate), ID (library), APW, Tare and Sample. Long presses open Units, the Menu (and audit trail), and related setup functions.

Set an average piece weight

If no APW is stored, the piece-weight and count windows show 0. To sample a new APW:

1. Place the sample on the pan (or tare a container first, then add the sample).
2. Type the sample size on the numeric keypad. The number appears in the count window. You can also press Sample, then type the size.
3. Press Sample. Dashes appear briefly, then the scale shows the APW and the count.

To enter a known APW, press APW, type the piece weight and press APW again. After a valid APW is stored, tare a container if you need one and keep adding parts; the count window updates as you go. Auto-optimization refines the APW as more pieces are added. For the RC31P15, keep the sample at or above 10 g (0.02 lb) and the APW at or above 0.05 g (0.0001 lb). The Wt Lo and APW Lo symbols light if you go below those recommendations.

Library, checkweighing and accumulation

The 30-item library stores a 12-digit part or SKU number, the APW, checkweighing or checkcounting targets, a tare and accumulated weight or count. Press ID to recall or edit a record. Checkweighing uses the three LEDs and an optional beeper; Target starts that mode. M+ accumulates displayed values manually or automatically, and can print a count of transactions. Accumulation in legal-for-trade mode totals only gross or only net weights, not both together (the scale shows NO.ACC if you mix them).

OHAUS Ranger Count 3000 calibration

The RC31P15 uses external calibration. A span calibration (zero plus a full-capacity mass) is recommended the first time you set the scale up, and again whenever accuracy slips. Linearity calibration adds a mid-point at half of capacity. Calibration weights are not included.

Span calibration, from the official manual:

1. Make sure the menu-lock / LFT switch under the scale is unlocked. The Calibration (C.A.L) menu is hidden when that switch is locked.
2. Have the correct mass ready: 15 kg / 30 lb for the RC31P15 (manual Table 4-1). If the active unit is g or kg, the scale calibrates in kg; if it is lb, oz or lb:oz, it calibrates in lb.
3. Press and hold Menu until MENU appears, then release. When C.A.L is shown, press Yes. When SpaN is shown, press Yes.
4. The display shows 0 kg (or 0 lb). Press Yes to store the zero reading (dashes appear while it saves).
5. Place the specified calibration mass on the pan. Press Yes to accept that weight, or No to choose an alternate allowed weight.
6. When the reading is stored, the display shows done and the scale returns to the previous mode. If you see CAL E, move the scale to a stable location, confirm the mass, and retry.

Linearity calibration (Lin1) stores zero, the mid-point (7.5 kg / 15 lb on the RC31P15) and full capacity; the mid-point mass is fixed. GEO (0–31, factory default 12) adjusts the calibration for your location if you use that method instead of a fresh span. A second platform, if the optional 2nd-scale kit is installed, has its own Zero2 / Span2 / Lin2 items.

For a certificate you can put in a quality file, have MNM Scales calibrate the RC31P15. Our TDA-registered technicians do the work in-house with NIST-tested weights before the scale ships, or nationwide by mail for a scale you already own. In-house calibration and NIST calibration are both available. Turnaround is usually 1–3 business days after we receive the scale.

Calibration	Price	Add to order
In-house calibration with certificate (NIST-tested weights)	$250	Add $250 calibration
NIST calibration with a NIST-traceable certificate	$595	Add $595 NIST calibration

Houston-area customers who want the work done at their site can schedule on-site calibration at $295 plus $2 per mile round trip, with the $250 or $595 calibration priced on top of that service call. See scale calibration in Houston or get a quote.

Is the RC31P15 NTEP and legal for trade?

Yes. The RC31P15 is NTEP. NCWM Certificate of Conformance 13-022A2 (Ohaus Corporation, models including RC31Px, non-computing scale, Accuracy Class III, nmax 3,000, −10 °C to 40 °C) is listed as Active in the NCWM certificate database. For the RC31P15 the certified increment (e) is 0.01 lb / 0.005 kg on a 30 lb / 15 kg capacity. The current A2 certificate, issued December 2, 2019, supersedes 13-022 and 13-022A1; an expired or superseded original still counts as NTEP, and this one remains Active. Measurement Canada approval, from the OHAUS datasheet, is AM-5907C. That makes the scale legal for trade for general-purpose weighing once it is placed in service under your state’s rules. In Texas, see our TDA scale certification guide, the legal-for-trade scale checker and what NTEP / legal for trade means.

The NTEP evaluation is for general-purpose weighing. Certificate 13-022A2 and the OHAUS datasheet both note that the counting feature is labeled not legal for trade. Weighing by weight at the certified increment is the approved trade function.

Before a weights-and-measures official or authorized service agent verifies and seals the scale, the manual requires you to confirm the menu settings, perform a calibration, then set the menu-lock switch under the scale to Locked. When that switch is locked, the Calibration menu is not accessible, several setup items freeze (zero range 2%, stable range 1d, auto-zero tracking 0.5d, stable-only on, lb:oz off, auto-print/continuous disabled). The switch can be secured with a paper seal, a wire seal or a plastic tie. Jurisdictions that use an audit trail can record the CFG and CAL event counters instead: press and hold Menu and release when AUDIT appears to read them as CFGxxx and CALxxx. MNM’s TDA-registered technicians can calibrate, verify and seal an RC31P15 as part of in-house or on-site service.

RC31P15 error codes

Code or symptom	Meaning	What to try
Cannot turn on	No power	Check the cord, outlet and voltage printed on the data label.
Poor accuracy	Needs calibration, or the bench is unstable	Level the scale, move it off drafts or vibration, then perform a span calibration.
Cannot calibrate	Unstable bench or the wrong mass	Use the 15 kg / 30 lb weight and a firm, draft-free surface.
Err 8.1 / 8.2	Power-on zero is above or below the allowed limit	Clear the pan, make sure nothing touches it, and restart.
Err 8.3	Over-range	Remove the load; stay within 30 lb / 15 kg (safe overload is 150% of capacity).
Err 8.4	Under-range on the RC31P15 (not a Scout-balance code)	The reading is below the underload limit. Check that the pan is seated and the scale is level.
Err 8.5	Tare out of range	Adjust the tare so it stays within capacity.
Err 8.6	Display overflow (more than 6 digits)	Reduce the displayed value or change the unit.
Err 9.5	Calibration data not present	Have an authorized OHAUS dealer perform a calibration.
CAL E	Calibration value out of limits, unstable, or wrong weight	Retry span calibration with the specified mass on a stable bench.
Lo.REF / rEF.Err	Reference (sample) weight is too small	Increase the sample toward the 10 g / 0.02 lb minimum for the RC31P15.
NO.ACC	Gross and net mixed in accumulation (LFT)	Accumulate only gross or only net weights.
lo.bat / flashing battery	Battery is low or empty	Connect AC power and charge the pack. Replacement is an authorized-dealer job.
——- (busy)	Tare, zero or print in progress	Wait for the action to finish.
–NO–	Action not allowed	The function is locked, disabled or not valid in the current mode.

Accessories and service

RS232 is built in. A 9-pin OHAUS RS232 cable (80500525) is in stock at $199 (regular $304) if you need a PC or printer lead (not included with the scale). Optional OHAUS kits listed in the manual include a second-scale input (30037446), Ethernet (30037447), a second RS232 (30037448), USB (30037449), a weigh-below hook (30037450) and an in-use cover (30037451). Get a quote if you want a kit added to an RC31P15 order.

MNM Scales is an authorized OHAUS dealer. We stock the RC31P15, ship free in the continental U.S., and have TDA-registered technicians on staff for in-house calibration, nationwide mail-in calibration and Houston-area on-site work. We also repair all brands and types of scales. Call (832) 290-3120 or request a quote. Browse OHAUS scales or counting scales.

Frequently asked questions

Where can I get the RC31P15 manual?

A printed OHAUS Ranger Count 3000 instruction manual ships in the box with the RC31P15 (OHAUS document 30037454). This guide walks through the setup, counting, library, calibration and error-code steps most shops need from that manual.

How do I calibrate the OHAUS RC31P15?

Unlock the menu-lock switch under the scale, press and hold Menu until C.A.L appears, press Yes, then Yes on Span. Confirm the zero reading, place the 15 kg / 30 lb calibration weight on the pan (not included), and press Yes. The display shows done when span calibration succeeds. For legal-for-trade use, calibrate before the menu-lock switch is sealed. MNM Scales, an authorized OHAUS dealer, offers in-house calibration with certificate for $250 or NIST calibration with a NIST-traceable certificate for $595, nationwide by mail, plus on-site service in the Houston area at $295 plus $2 per mile round trip.

What calibration weight does the RC31P15 need?

The official Ranger Count 3000 manual (Table 4-1) specifies a 15 kg / 30 lb span mass for the 15,000 g / 30 lb RC31P15. When the active unit is g or kg, the scale calibrates in kg; when the active unit is lb, oz or lb:oz, it calibrates in lb. The weight is sold separately and is not included with the scale. Linearity calibration uses a fixed mid-point at half of full capacity (7.5 kg / 15 lb) plus the full-capacity mass.

Is the OHAUS RC31P15 NTEP?

Yes. The RC31P15 is NTEP Class III under Certificate of Conformance 13-022A2 (RC31Px family, 30 lb / 15 kg, e = 0.01 lb / 0.005 kg, nmax 3,000, Active). Measurement Canada approval is AM-5907C. The approval covers general-purpose weighing. The certificate and the OHAUS datasheet note that the counting feature is labeled not legal for trade.

How do I set an average piece weight on the RC31P15?

Place the sample on the pan, type the sample size on the numeric keypad, and press Sample. The scale displays the APW and the count. You can also press APW and type a known piece weight. For the RC31P15, the minimum recommended sample weight is 10 g (0.02 lb) and the minimum recommended APW is 0.05 g (0.0001 lb). The Wt Lo and APW Lo symbols light if the sample or piece weight is below those recommendations.

What does CAL E mean on a Ranger Count 3000?

CAL E is a calibration error: the value is outside allowed limits, the environment is unstable, or the wrong calibration weight was used. Move the scale to a firm, draft-free surface, use the 15 kg / 30 lb mass specified for the RC31P15, and retry span calibration. If CAL E stays on, or you see Err 9.5 (calibration data not present), have an authorized OHAUS dealer calibrate it. Err 8.4 on this model is an under-range error, not a Scout-balance code.