Low signal power with Bolt

I am using two Bolts to connect a machine to the network at a distance of 3 meters. The RSSI is very variable between -50 and -75 and there are occasional communication cuts. In this room, we know that there is a lot of electromagnetic reflection, there is metal and there is humidity. The best setup is with ATS3002 = 8 at the access point, but it’s far from perfect. How can we improve the performance of our antennas? You can see the setup on picture.

Thank you

Could you potentially try and connect over bluetooth and see if that seems to be more reliable?

I’ll give it a try, but I know our IT department isn’t too keen on the idea. Is the Bluetooth network more efficient in an environment where there is a lot of thought?

If the issue is that there’s a lot of traffic on the 2.4 and 5GHz frequencies in that area, it might be useful. It will be slower than the current connection that is being used but it may be more reliable if there’s less noise that’s interfering at that location.

Hi Tim

I tried the bluetooth network and was able to read an RSSi of -45, sensing the same result. The bolts are alone on the 5Ghz frequency to do a machine start / stop only, there is no other communication on the network. I have never been able to establish a connection with 2.4GHz. Connectivity is the issue, RSSI varies a lot from day to day. This room has been appraised and presents a lot of reflexion. All the RF systems in our factory had to adapt to this problem. Some days look like this (see photo). Can the Bolts be adapted to this type of situation?

Hi @Maxi,

Can you check and make sure that the bolts are on the most recent firmware


and show me how the bolts are mounted in those enclosures? Are they both facing straight up?

Also what is causing this interference that you were mentioning?

Thanks for the tip, I didn’t know there was an update newer than 2.03.02. After the update, the RSSI has remained around -60 today. The antennas are not in the vertical position in the PVC boxes. I didn’t see any impact based on their orientation. The antennas are only 4m away. The Bolt access point signal strength has been measured by other types of antennas and is very good. I believe the interference comes from and electromagnetic reflection. It’s when the waves bounce off so much reflective walls like metal that they end up making telecommunications difficult. An expertise has been made and we have this type of problem, it is common in food factories because, everything is metal, walls, ceiling, machines … Some telecom companies will use a dipole antenna arrangement with a differential telecommunication to filter the signal. Is the Bolt equipped to handle this type of environment?

Tanks for support

Depending on how these are facing the orientation may be an issue. This is the typical setup that we recommend along with showing their propagation patterns.




If the bolts are facing away from each other I could see that being an issue. One other thing I was wondering was if the bolts are out of the enclosures are they still having these issues?


Hi Tim
The Bolts are installed face to face. Today I took the two bolts out of their PVC boxes and oriented them vertically at 0 ° and 90 °. The RSSI went from -60 to -55. It’s better but, it’s weak for an antenna that is only 14 feet away. Signal strength is still not constant. I also tested the signal strength of the access point. I plugged the Bolt client into my laptop and walked around the factory, through two plastic doors and over 50 feet was not enough to lose signal. The signal broke behind a concrete wall, I think it is good and more power than I need! Unfortunately, this does not change my signal cut problem. By the way, is RSSI = dbm?

Hi Maxi,

You might be able to play with the Max Radio Output power to try and get a better control of the strength.

However if the level of noise is that bad in that area, then there may not be much we can do here to help maintain communication between the devices

RSSI is a relative index, while dBm is an absolute number representing power levels in mW (milliwatts)

One of my other colleagues suggested that it may be worth using the ABW Bridge II and faced them together, mounted on metal backplates to try to eliminate noise.

Hi Maxi,

Is this still an issue?


Hi Tim,

Here are the results of my tests

Bluetoot ATS2011 = 20 RSSI = -57

ATS2011 = -20 RSSI = -54

WLAN ATS3001 = 8 RSSI = -54 This is the best result over a month of trying

When I activate the antennas the RSSI is = -15 and gradually goes up to around -54. The transition last a few seconds.

Intriguingly, when I do a wlan scan it picks up the PC network antenna at RSSI = -39 and that antenna is twice as far away.

I also know that the power of this PC antenna has been reduced to its maximum.

Can we decrease the power lower than -25dbm?

The distance to cover is very short

Tanks for support







Hi Maxi,

Unfortunately it doesn’t look like we’re able to go less than -25dBm.

If you were to move both of these devices to a different location temporarilly do they still have this connection issue this close or does this just seem to be happening at this location. If it’s just at this location I’m not sure what else we’ll be able to do due to the noise in the area.


Hi Tim,

For the past three months I have tried several different physical configurations and found that the signal quality varied significantly depending on its location and the ambient humidity. When I moved the antennas to a room without water and metal the communication was good. Can a Bolt configured as a client communicate with an antenna that is not an Anybus product and is configured as an access point?

A bolt should be able to connect to a 2.4 or 5GHz access point. I believe you should just need to hit the scan button and then select the wireless access point you want to connect to along with any password information.