How do I improve the WiFi connection between my total station and tablet?

Wi-Fi is used to connect the PLT head unit to the controller. Use this article to troubleshoot Wi-Fi connectivity problems you may be facing.

Step 1: Make sure your tool and tablet are up to date

Please see this article for more information on updates. Tablet software and tool firmware required updates may be affecting Wi-Fi connection stability.

Step 2: Adjust the Wi-Fi Connection

When a Wi-Fi connection is established, the tool continues using that channel until it reconnects. For PLT 300 users, simply restart the HCL software and reconnect the tool and see if Wi-Fi improves with a refreshed connection. The PLT 300 always automatically finds the most stable Wi-Fi channel at the moment of connection.

For PLT 400 users, follow these steps if performance becomes poor after moving around the jobsite:

Go to Settings > Tool and Connection
Under "WiFi channel," toggle the tool between "Auto 2.4 GHz" and "Auto 5GHz"

2.4 GHz is typically best for most use cases. 5GHz can occasionally be an ideal back-up option (more on this below).

You will see a message indicating it may take time to reconnect.

Once confirmed, you will hear a short chirping beep from the head unit, followed by a loading icon until connection is reestablished. The tool will attempt to connect using the strongest channel it finds in the new location according to the GHz selection you chose.

Step 3: Check the environment around your tool

The physical environment can affect the Wi-Fi connection between the tablet and total station. You do not need to create a completely clear jobsite, but pay attention to what is directly between and immediately around the tablet and total station.

Check these three things:

1. Keep the path between the tablet and tool as clear as practical

Try to avoid positioning large obstacles directly between the tablet and total station, particularly:

Steel structures
Reinforced concrete
Large machinery or vehicles
Walls or floors

You don't need a perfectly empty working area. The goal is simply to give the tablet and total station the clearest practical path to one another.

In addition, attempt, as practically as possible, to keep the tablet and total station on the same horizontal plane to improve signal connection strength at further distances.

2. If the connection is poor, change your position

Radio signals interact with the surrounding environment, so a connection can sometimes change when the tablet or total station is repositioned.

If practical:

Move the tablet to a slightly different position.
Try moving the total station to another suitable setup location.
Reconnect and check whether performance improves.

A small position change can be a useful troubleshooting test. If connection quality changes noticeably after repositioning, the local environment may be contributing to the problem.

3. Pay attention to nearby wireless activity

If many Wi-Fi networks or wireless devices are operating nearby, the available radio spectrum may be congested.

This is particularly relevant in locations such as:

Large active jobsites
Office buildings
Hospitals
Industrial facilities
Dense urban environments

If you suspect congestion, return to Step 2 and try an alternative Wi-Fi channel or band where available.

Still having problems? Try these options

Option 1: Stop the video feed (PLT 400 only)

On the PLT 400, go to Tool and Connection and select Stop Video.

The PLT 400's video feature uses significant Wi-Fi bandwidth because the video feed runs in the background to support camera-based functionality. Stopping the video reduces the amount of data being transmitted and can improve connection range and performance.

Trade-off: When you need the camera again, the video may take a few moments to appear while the camera feed starts.

Option 2: Try Bluetooth (PLT 400 only)

For the PLT 400, Bluetooth may be an alternative when:

You want a stable connection.
You don't need the video feed.
You need greater distance between the tablet and head unit.

Bluetooth cannot transmit the video feed, but the possible distance between the tablet and head unit is greater. Using Bluetooth requires the POA 68 Bluetooth extender, which is not available in all markets. Contact your Hilti sales representative regarding availability.

A Brief Explanation: Strong Signal, but Poor Signal Quality

Wi-Fi may offer a very strong signal, but the quality may still be poor. To understand this, Wi-Fi, especially in an area with many wireless devices, can be similar to a person communicating within a crowded room. The person next to them may be very easy to hear (you can identify their voice and the direction from which it comes), but what they are saying may need to be repeated several times until their message is clear.

This is very similar to what happens with Wi-Fi in a congested wireless space: strong signal, but poor quality. The tablet may receive a strong signal from the PLT, but interference from other wireless activity can make reliable communication more difficult.

Can I identify Wi-Fi congestion on the jobsite?

Wi-Fi analyzer applications for smartphones and PCs can inspect Wi-Fi channels in the surrounding area and help identify less congested network configurations. This could be helpful if congestion is a problem you often encounter.

What about areas without wireless congestion?

An open jobsite with little nearby wireless traffic and good line of sight generally provides favorable conditions for a 2.4 GHz Wi-Fi connection. Why, then, could Wi-Fi connection issues occur?

Imagine, now, a concert hall: someone shouts commands to another person at an opposite end of the hall. Acoustically, the sound will bounce off walls, the ceiling, and may not come in clearly to the person on the other end.

Similarly, in an open area, the Wi-Fi signal can reach the receiving antenna via different paths. The physical surroundings influence how radio energy gets from one antenna to the other.

Put another way: Wi-Fi is not like shooting an arrow. It will not travel in a single-line trajectory to its target. Wi-Fi interacts with the environment similar to light - it travels in waves. So, imagine how light illuminates a room. Likewise, Wi-Fi travels outward, interacts and reflects within the environment, and finally some or most of the energy from that signal finds its target.

If connection problems occur in these conditions, wireless congestion becomes a less likely explanation. Check the other troubleshooting factors in this article, including reconnecting the tool and tablet, repositioning the devices, confirming current software and firmware, and testing alternative connection settings available for the tool.

If connection problems continue under otherwise favorable conditions, the problem may require further investigation rather than repeated Wi-Fi channel changes.

Should I use 2.4 GHz or 5 GHz?

Both 2.4 GHz and 5 GHz can provide a good connection between the tablet and total station. The best option depends on your working distance and the amount of wireless traffic around the jobsite.

As a general rule:

Choose 2.4 GHz as a default setting and/or when you need more range.
Try 5 GHz when you need more stability in a congested area.

2.4 GHz: Better for longer range

2.4 GHz is the ideal Wi-Fi option in HCL and is generally the best place to start. It provides greater working range between the tablet and total station and generally supports a better video connection.

Consider staying on 2.4 GHz when:

Your current connection is working well.
You need greater distance between the tablet and total station.
You are working in an area without significant Wi-Fi congestion.

Why can 2.4 GHz sometimes become unstable?

The 2.4 GHz frequency is commonly used by Wi-Fi and other wireless devices. Although multiple 2.4 GHz Wi-Fi channels exist, neighboring channels can overlap with one another.

What this means on the jobsite:
In an area with many wireless devices or Wi-Fi networks, there may be more competition for the available wireless space. You may therefore experience an unstable connection even when the tablet and total station are relatively close together.

If this happens, the steps mentioned above likely can assist in improving performance: reconnecting the tool, trying another available channel, or changing to 5 GHz.

5 GHz: Better for congested areas

5 GHz provides more non-overlapping channel options than 2.4 GHz. In practical terms, this gives the total station more opportunities to operate without competing with nearby Wi-Fi traffic. However, the trade-off is shorter working range between the tablet and total station.

Consider trying 5 GHz when:

Your 2.4 GHz connection is unstable.
There are many Wi-Fi networks around the jobsite.
You are working over a relatively short distance.
Changing the 2.4 GHz channel has not resolved the problem.

Important: available channels depend on your country

Not every Wi-Fi channel can legally be used in every country.

The PLT 400 only presents channels permitted for the configured country/region. Because Wi-Fi regulations can change, keeping the instrument firmware/software current is important for maintaining the appropriate regional channel configuration. In addition, utilizing the "auto" Wi-Fi connection for the various frequency channels is generally recommended.

See this article for more information regarding tool updates.