Today’s grade lasers offer an incredible combination of power, accuracy and features, at a much lower cost than before. As there are many brands and models available, informed buyers are in the best position to select an instrument with the features they need without spending more than necessary.
Grade Lasers (sometimes called slope lasers) allow a rotating laser plane to be sloped to a specified grade. Grade lasers facilitate accurate and fast operations over a wide area, and are used with a laser receiver attached to a grade rod or mounted on heavy equipment for laser machine control. Some grade laser levels allow one axis to be sloped and some facilitate sloping both the x and y axes.
The price of new grade lasers is dictated by power, features and durability. Grade lasers by the quality producers are priced from about $2000 for single axis and $2400 for dual axis, up to $4500 for single axis and $7000 for dual axis. The finest grade lasers are from Trimble Spectra Precision, Trimble Apache, Leica, AGL, Agatec and Topcon, as they invest heavily in research and development and are the industry drivers of product innovation. Used units by these manufacturers that have been well cared for are a good value.
Grade laser technical parameters, specifications and characteristics include the following:
- Auto-levelling capability: All new grade laser levels automatically level when the instrument is set up within the auto-levelling range (usually ± 5°).
- Level & grade accuracy means the accuracy attainable at a certain distance from the transmitter – typically ± 1/8” at 100’ for grade settings and ± 1/16” at 100’ for level.
- Display & controls: Display screen resolution, character size and back-lighting is important as are clear menu and command functions.
- Grade indication is the numerical accuracy of grade setting [often down to one thousandth of a percent (.001%)].
- Grade capability refers to whether single or dual axis grade, and the maximum slope or grade range (% up and down) that can be set. Some units are capable of steep to very steep slopes (25% or more)
- Operating range is the distance a receiver can be from transmitter (1000’ to about 1500’ for the higher end units with a suitable receiver).
- Operating temperature range means that the grade laser will function properly within the specified range of temperature, with a broader range providing more user flexibility in hot or cold conditions.
- Weather protection standards define the degree an instrument can withstand adverse environmental conditions. Lower priced units are often manufactured to IP54 standard (water resistant) where the higher priced units are to a higher standard such as IP66 and IP67 (dust and waterproof).
- Housing ruggedness: While grade lasers should be handled with care, sometimes job-site conditions are tough, so a robust instrument housing provides added durability to resist external impacts (including better lighthouse protection) as well as protect internal electro-optical components with dampening (shock absorbing) measures..
- Rotation speed: The user can set the rotation speed from 0 rpm (pointing mode) up to 900 rpm, either incrementally or with variable settings
- Power supply: Depending on make and model, there are different ways that grade lasers can be powered, namely with disposable batteries (usually alkaline) rechargeable (usually NiMH), or the inherent flexibility to accommodate both. Rechargeable capability is desirable if used often and/or for extended periods of time (though the operating time between recharge cycles is shorter). ON some models there are provisions for using a 12v power cable for connection to a vehicle battery.
Recommended Grade Laser
The Spectra Precision GL412N is the best Single Grade Laser on the market today. Highest level of accuracy, the strongest compensator to allow for constant use without drifting to occur and highly drop protected. The GL412N has a in-grade levelling compensator as well, this means that when you put in a single grade you can trust the grade for the whole day, no drifting and no weather issues only a solid Single Grade Laser. This laser is excellent for Plumbing, Trenching and single grade operations.
The Spectra Precision GL422N is the big brother of the GL412N, The same internals are within this Grade Laser the only change is the fact it has a Dual Grade setting in it. Allowing you to be able to do all your dual grade jobs such as major earthworks, civil sites, car parks and runoffs.
The Spectra Precision GL622N is the super upgraded GL422N. It is Heavier, Bigger, Stronger and more Robust then the GL422N. If you find yourself elevating your laser on an 3M elevating tripod using it for grade control or over super long distances for Agricultural purposes then this is the grade laser you require. With 25% +/- Grade Range you can be sure the GL622N will be able to complete any tasks you require it to.
The Final Grade Laser we would recommend is the specialised UL633N Dual Grade Laser. The big change from the GL622N to the UL633N is the Pipe Laser function the UL633N has. If you are laying pipes this is a 2 in 1 laser no longer do you require to purchase an expensive Pipe Laser and an Expensive Dual Grade Laser. The UL633N has you covered in that field.
Grade Laser Features That May be Available
Grade match is a feature that provides the ability to project a grade from the instrument set-up location to any unobstructed remote point. Once the grade at the remote point is matched, it can be projected across any area within the range of the grade laser. Units with a remote control will facilitate this operation remotely and some instruments will communicate with receivers and automatically seek, lock onto and then display the grade at the remote point.
Out of level warning light [sometimes called HI (height of instrument) warning] informs the user that the grade laser set-up was disturbed, so measurements may no longer be accurate. Some systems will also transmit the HI warning to the receiver (when so integrated). It is common for units to respond to an out of level warning signal by stopping laser rotation and turning the unit off to help prevent erroneous measurements.
Suitability for machine control: Grade lasers are designed for machine control applications. Higher priced units are not only more powerful, but incorporate advanced features to facilitate complex grade work and ensure beam stability under potentially tough job-site conditions (ground shaking and vibration) while working.
Remote control capability: Many grade laser levels are enabled with remote capability that is very helpful to have, particularly if one person is doing the set-up work. Note that the range of remote controls for grade lasers is usually around 300’ (far less than operating range distance), but longer range remotes (up to 500’) are available on certain high end units.
Temperature compensation is a feature that minimises the effects of temperature on critical grade laser functions, namely the laser output, beam stability, auto-levelling and grade stability.
Low battery warning is a common feature that gives the user advance warning that power is running low so the user has time to replace batteries or battery pack.
Plane lock is a feature that is beneficial for grade work where maximum stability and accuracy are required, preventing beam drift that could occur by allowing the laser plane to remain locked on a fixed location laser receiver so the laser plane will maintain stability regardless of wind and significant temperature changes.
Automatic axis alignment is a feature to simplify setup by allowing one person to roughly align an instrument to a grade axis and, by using a remote, direct the laser to align the axis precisely to the desired remote point.
Manual alignment sighting facilitates the set-up process by allowing instrument alignment to visual points.
Mask mode allows the user to turn off the laser signal in specified quadrants (up to three) so the laser does not interfere with others on the job-site who may be using lasers or when there are reflective surfaces (e.g., window glass) that could cause erroneous readings.
Grade bump is a capability that allows the user to remotely adjust (increase or decrease) the grade remotely.
Grade reverse (or grade swap) function allows a slope to be matched in the opposite (180°) direction.
Vertical Mode: Most lasers allow set-up in the vertical mode for plumb work.