SCM Technologies developed the CS-100 Cell Switch™ to enable pilots to remotely control 120-volt powered devices by plugging them into the Cell Switch™ unit and utilizing existing cellular networks to control and monitor them. This product is very useful to pilots, in the case of preheating your engine, because it can indicate when an aircraft engine has reached manufacturer suggested preheating levels. It is a proven fact that preheating an aircraft engine before flight during the cold weather months increases the longevity of the engine. In extremely low temperatures, oil congeals, battery capacity is lowered, and the engine starter can be overworked. Improper cold weather starting can result in abnormal engine wear, reduced performance, and shortened TBO time, or failure for the engine to work properly. Engines should be properly preheated several hours prior to departure, according to engine manufacturer regulations, and this is where the CS-100 Cell Switch™ comes in.
Gentlemen, Start Your Engines
The Cell Switch™ utilizes existing cellular networks to allow users to remotely control any device, such as an engine preheater, by simply plugging the device into the Cell Switch™ unit. You activate the preheater by calling the unit using an authorized phone number. The Cell Switch™ can be programmed to switch-on for a predetermined length of time whenever the unit is called and can be switched on or off by sending the unit a text message. This saves time and allows pilots to operate their aircraft safely.
Sounds Good, How Does It Work?
The first step in activating your Cell Switch™ is setting up cell service. It is recommended by SCM Technologies to use a T-Mobile® Prepaid Pay As You Go plan. This plan will provide you with one of T-Mobile’s® SIM cards and a phone number for the unit. SCM Technologies works closely with a corporate T-Mobile® store (#9892) that can set up an account for you and send you a SIM card for the unit. If you prefer using a local T-Mobile® store, it is recommended to visit the actual store location to make sure they set up the account correctly.
The mobile phone SIM card needs to have enough credit on it to send confirmation text messages when programming the Cell Switch™. It is recommended to use a SIM card with unlimited nationwide messaging.
Important: Make sure to remove the PIN request from the SIM card before inserting it in the unit; otherwise the device will not work. This can be done by the SIM card provider or by inserting the SIM card in a T-Mobile® phone and disabling the PIN request and the Voicemail function. It is important to make sure that the voicemail does not pick up the call.
To install the Cell Switch™, you need to mount the unit within close proximity of a 120-volt power supply and the device you wish to control, which in this case is your preheater. Once the Cell Switch™ has been mounted and connected to your preheater, you can install the SIM card and the antenna (see diagram below).
Once the SIM card and antenna have been installed, plug the unit into the wall and switch it on. The signal indicator (see diagram below) will flash green until it finds and logs onto the network. After it logs on, it will flash green every 3 seconds. If this does not happen then the unit is not logged on and may require an extension antennae or alternative network provider.
Once the unit has logged onto the network, you will need to test the connection. Plug a lamp (or any item you can physically see turning on and off) into the power plug on the unit. Call the number you were given from T-Mobile® for the SIM card from your cell phone. The unit will pick up your call and hang up. The lamp will turn on for 1 second and then turn off.
Next, you need to establish the signal strength of the location where the Cell Switch™ is installed. This will ensure the reliability of the Cell Switch™. To test the signal strength, send the following SMS text message to the unit from your cell phone:
Important: All SMS text messages must be sent in CAPITAL LETTERS. Do not add spaces or any other characters otherwise the system will ignore the commands.
The unit will send back a report to indicate the signal strength of the location of the Cell Switch™ which will look like this:
SIGNAL STRENGTH <14>
The number can vary from <3-31>. A consistent signal strength should be at least <12> and above. If the signal drops below <5>, it may log off the network and turn off the relay. This will give the appearance that the unit is not working or faulty, but it is programmed to turn off if the cell signal is lost for safety reasons. If this occurs, try relocating the unit to acquire a better signal.
I Command You
The Cell Switch™ is programmed by sending SMS text messages from your mobile phone to the telephone number you were given for the SIM card. All text messages are password protected. This means any text message, or command, you send from your phone must have the following prefix:
*PSSW12345 (This is the factory default password)
If you would like to change the password to another 5 digit number, send the following text message to the unit:
*PSSW12345*NPW=54321 (or whatever you want the 5 digit password to be)
You will receive the following message back from the unit to confirm the password has been changed:
The Cell Switch™ comes preset to turn (the relay) on for a period of 1 second. To change this time to, say, 1 hour you would use the following text message:
*PSSW12345*RLY=03600 (3600 seconds = 1 hour)
Important: Time is configured in seconds and is written as a 5 digit number, which is why 1 hour would be sent as 03600.
You will receive the following message back from the unit:
RELAY SET – 03600 (the unit will then turn on for 1 hour whenever it is called)
If you want to permanently turn the unit on or off, send one of the following text messages to the unit:
*PSSW12345*RLYP=ON or *PSSW12345*RLYP=OFF
You will receive one of the following messages back from the unit:
RELAY <P> ON or RELAY <P> OFF
There Can Only Be One
The Cell Switch™ can program one administrator number into the system. The administrator number will be recognized as the authorized number that has programming access to the system, as well as the ability to activate the device it is connected to. To add your number as the administrator’s number (for example 0-123-456-7890), you would send the following text message to the unit:
It is also possible to program up to 250 land line or mobile phone numbers into the system that will be recognized as authorized numbers that can access the system and activate whatever device it is connected to. Any unauthorized numbers calling the unit will result in the system rejecting the call and refusing access to the system.
These Are a Few of My Favorite Things
Setting passwords and turning the unit on and off are just a few of the functions the user can perform by sending a simple text message. Along with these, you can also:
- Monitor how long the unit has been on
- Turn the unit on for a selected period of time
- Configure security settings
- Configure the unit to turn on automatically up to twice a day
- Set the system clock
- Remote antennas available
While we discussed preheating your aircraft in this article as an example of what the Cell Switch™ can do, there are also a number of additional applications such as:
- Boating applications
- Camper preheaters
- Second home or cabin heat control
- Security lighting
- Automated gate control
- Storage unit security access
- Airport security access
- Server rebooting
- Temperature control and monitoring
- Access control and monitoring
Have you used the Cell Switch or know anyone who has? Comment below and let us know.
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