KRL-310 Red Rotary Laser with LP500: A Site Leveling Guide

The Mountlaser KRL-310 red rotary laser kit pairs a horizontal rotary laser with an LP500 receiver. Use it to transfer a common elevation across concrete forms, floor preparation, or a site pad. Set the laser on a stable tripod, take a reading at a known benchmark, and compare the remaining points with that same reference.

When to use the KRL-310 with LP500

The KRL-310 is suited to horizontal elevation checks. The LP500 detects the rotating red beam so you can find the plane with a grade rod when the beam is hard to see. Its clamp holds the receiver on the rod while you read the scale.

• Concrete formwork: Check the corners, openings, and intermediate points on long runs before a pour.
• Floor preparation: Take readings across a marked grid and use the same points to check high and low spots after adjustments.
• Site elevation checks: Compare points on a pad or excavation with the job benchmark. For a designed slope, use the target elevation at each station on the plan.

How to set up the laser and receiver

1. Secure the laser to a tripod on firm ground with a clear path to the work points.
2. Let the laser settle in its horizontal leveling mode. Follow the indicators in the instructions supplied with the kit.
3. Stand the grade rod upright on a known benchmark. Face the LP500 detection window toward the laser and slide the receiver until it indicates on-grade. Record that rod reading.
4. Repeat the reading at each work point. On a conventional rod whose scale increases upward, a larger reading indicates a lower point.
5. Return to the benchmark after a set of readings or if the tripod is disturbed. If the original reading changes, establish the reference again and recheck the affected points.

Example: checking slab forms before a pour

Suppose the LP500 centers at 1.25 m on the benchmark and the top of the slab should be at the same elevation. A corner reading of 1.27 m places that point 20 mm below the target. A reading of 1.23 m puts it 20 mm above. On a slab with designed fall, work from the individual target elevation at each point. Record the targets so another crew member can repeat the check.

What to compare before you order

Mountlaser lists the KRL-310 with the LP500 at a rated working diameter of 800 m and a leveling accuracy of ±0.5 mm at 10 m. The diameter is the full span with the instrument near the center. A rated 800 m diameter corresponds to a 400 m radius under the rated conditions. Confirm the actual working distance on site before relying on it, especially where machinery or structures can interrupt the beam.

Check the kit contents on the product page and confirm whether you already have a suitable tripod and rod. If your work requires vertical layout or a receiver that shows a numeric height offset, compare the options in the Mountlaser rotary laser collection.

Frequently asked questions

Is this the red or green KRL-310?

This guide covers the red-beam KRL-310 kit sold with the LP500 receiver.

How do I check a reading that looks wrong?

Repeat the benchmark reading first. If it matches, check that the rod is upright, the clamp is secure, and the detection window faces the laser. If the benchmark has changed, establish the reference again.

Can I use it outdoors?

Use the included LP500 to detect the beam. Choose a stable tripod location and keep the path to the receiver clear.

View the KRL-310 red rotary laser kit with LP500 to check current availability and order. Contact Mountlaser if you need help choosing the rod, tripod, or receiver for your setup.