Spectra Precision GL422N-14 Dual Grade Laser w/ CR700 Receiver

Overview

The Spectra Precision GL422N-14 represents a specialized solution for contractors facing multi-directional grading challenges that single-slope lasers cannot efficiently address. This dual-grade rotary laser simultaneously establishes independent X- and Y-axis slopes, eliminating the repositioning, mathematical interpolation, and verification shots required when building complex drainage planes or crowned surfaces with single-axis equipment. Bundled with the CR700 machine receiver, the GL422N-14 delivers the closed-loop grade control necessary for GPS-denied environments, confined sites, or projects where laser-based systems provide faster setup than RTK networks. The unit's IP68-rated construction and shock-mounted optical assembly handle the transport vibration and environmental exposure common to earthmoving operations, while the 14% grade capacity accommodates steep utility trenches and parking structure ramps that exceed conventional laser limitations.

Key Specifications

• Grade Range: ±14% on both X and Y axes (independent slope control)
• Accuracy: ±3/32" at 100 feet (±2.4 mm at 30 m)
• Beam Diameter: 2.4 mm at 30 m
• Rotation Speed: 600 RPM (variable speed compatible with older receivers)
• Working Diameter: 2,600 feet (800 m) with CR700 receiver
• Self-Leveling Range: ±5° on both axes
• Operating Temperature: -4°F to 122°F (-20°C to 50°C)
• Environmental Rating: IP68 (dust-tight, submersible to 3 feet)
• Power: Rechargeable NiMH battery (40-hour runtime) or alkaline D-cells
• Remote Control Range: RC703 remote included, 300-foot functional range

What's in the Kit

• GL422N-14 dual-grade laser transmitter with rechargeable battery
• CR700 machine receiver with rod/grade stake mount
• RC703 remote control with belt holster
• Heavy-duty transit case with die-cut foam (field-replaceable insert)
• 110V battery charger with international plug adapters
• Grade entry template and axis alignment target
• Printed quick-start guide and calibration certificate

Job Applications

• Crowned Parking Lots & Multi-Slope Pads: Establish the longitudinal slope for drainage and the perpendicular crown simultaneously, eliminating the interpolation and staking density required when working from single-axis control. Reduces layout time by 60-70% on complex parking structures with multiple drainage zones.
• Asymmetrical Drainage Swales: Set independent fall directions where swales transition from symmetrical to offset configurations, common in roadway median work and bioretention cells. The dual-axis control maintains design elevations through geometry changes without repositioning the laser.
• Building Pads with Cross-Fall: Grade industrial slabs and warehouse floors requiring drainage toward corner drains or trench systems—applications where the slab must fall in two directions from high point to low point. Single setup replaces the string-line networks or multiple laser positions previously required.
• Roadway Cross-Sections & Superelevation Transitions: Control the transition zones where roadways shift from normal crown to superelevated (banked) curves, maintaining precise elevation control across the full pavement width as the cross-slope rotates through the spiral.
• Recreational Surface Grading: Build athletic fields, golf course features, and engineered slopes requiring multi-directional drainage away from play surfaces. The dual-grade capability replicates design intent without the survey-intensive staking that single-slope systems demand on organic geometries.
• Trench & Utility Corridors with Lateral Slopes: Install pipe runs with design fall while maintaining lateral slopes for trench safety or site drainage, particularly in wetland crossings or flood-zone work where trench floors must shed water perpendicular to pipe alignment.

Compatible Accessories

HL760 Digital Handheld Receiver | Rod-Eye 180 Receiver | C59 Telescoping Grade Rod | Heavy-Duty Flat-Head Tripod | Alkaline D-Cell Battery Tray | LP40 Laser Plumb Adapter

Related Guides

Dual-Grade Laser Setup Procedure | Dual-Slope vs. Single-Slope Laser Comparison | Machine Receiver Calibration & Verification | Rotary Laser Accuracy Troubleshooting

Frequently Asked Questions

Can the GL422N-14 operate in single-slope mode if I only need grade in one direction?

Yes. The laser functions as a full-featured single-grade system when you set one axis to 0% slope. This flexibility allows you to use the same unit across simple and complex jobs without carrying multiple lasers. The RC703 remote lets you switch between single- and dual-grade modes without returning to the transmitter.

What's the practical grade accuracy I should expect on a 300-foot parking lot using this system?

At 300 feet, the ±3/32" per 100' specification yields approximately ±9/32" cumulative accuracy (±7 mm) under field conditions, assuming proper setup and receiver calibration. Actual results depend on setup rigor, atmospheric conditions, and whether you're verifying with the CR700 on a stable mount versus a handheld receiver. For tighter tolerance work, reduce the working radius or verify with total station checks at grade breaks.

How does the CR700 receiver differ from standard rod-mounted receivers like the HL760?

The CR700 is a machine receiver designed for continuous grade control on dozers, motor graders, and excavators—it outputs to machine control systems rather than providing visual/audible indication for hand grading. If you're doing manual grading with a skid steer or checking elevations with a grade rod, you'll need to add an HL760 or Rod-Eye receiver. The CR700 included in this kit is valuable for equipment-based finish grading but won't replace handheld receivers for layout verification.

Will this laser work with my existing Trimble or Topcon machine control system?

The GL422N-14 transmits a standard rotating laser plane—the compatibility question centers on the receiver and control box, not the laser itself. The included CR700 is Spectra-proprietary and interfaces with Spectra control systems. If you're running Trimble Earthworks or Topcon 3D-MC2, you'll use your existing laser receivers with the GL422N-14 transmitter; the laser plane itself is universally detectable. Contact your machine control provider to confirm receiver compatibility with dual-grade laser configurations.