The SAA Field Power Unit (SAAFPU) is a portable unit designed to provide power to the ShapeArray (SAA). It also converts communications protocols to allow for communication via USB between the ShapeArray and a PC running SAARecorder software, or an Android device running SAADroid. It is designed for use when data is manually collected from a ShapeArray in the field or in the office.

Step 1 - Charge the SAAFPU

Measurand's SAAFPU contains a 12 V, 6 or 7 aH non-spillable battery (battery capacity varies by model). Once charged, this battery can operate a 40 m ShapeArray continuously for over 10 hours. Measurand recommends that you fully charge your SAAFPU prior to usage in the field. To charge the battery, connect the three prong power connector to a mains power source. The battery meter on the main panel of the SAAFPU can be used to check charge.

WARNING: The battery meter on SAAFPUs Model 005 R.5B and newer will not turn off automatically and, if left on, will slowly drain the battery. Please turn off the battery meter after use by pressing the ON button a second time.

Figure 1: A model 5 SAAFPU - the three prong power connector is used for grounding and charging and the battery meter can be used to check the battery's charge

Step 2 - Connect the SAAFPU to the Ground

Measurand recommends connecting the SAAFPU to the ground before connecting the ShapeArray or the computer for taking readings in the field. This can be accomplished either by plugging in the three prong power connector to a mains power source or by connecting the grounding plug on the left side of the unit to a grounding rod.

Figure 2: The left side of an SAAFPU has a grounding plug and a 4-pin connector for connecting a ShapeArray

Step 3 - Connect the SAA to the SAAFPU

Power to the ShapeArray is controlled via SAARecorder or SAADroid. The following steps should be taken when using the SAAFPU with a ShapeArray. Connect the ShapeArray to the SAAFPU with the 4-pin circular connector (Amphenol connector), or the 5-pin terminal block (Phoenix connector).

Figure 3: An SAAFPU - (A) Amphenol connector interface diagram, (B) Phoenix connector interface, (C) Battery indicator, and (D) Auxiliary 12 V Battery connector

Note: Only one ShapeArray can be connected to the SAAFPU at one time. Two or more ShapeArrays cannot be connected to the SAAFPU at one time!

The wiring for the 4-pin circular (Amphenol) connector is shown in the figure below.

Figure 4: Wiring for the 4-pin circular (Amphenol) connector on the ShapeArray cable

The wiring for a 5-pin terminal block (Phoenix) connector is shown in the figure below.

Figure 5: Wiring for a 5-pin terminal block (Phoenix connector) on the ShapeArray cable

Step 4 - Connect the SAAFPU to the PC Directly

Connect the serial to USB cable provided with the SAAFPU, Figure 6.A below, to the serial connector on the front facing plate of the SAAFPU, Figure 6.C below. Once this is done, plug the USB connector into a USB port on the PC. 

Note: The serial connection does not have any screws because it is meant to act as a quick release point in case the cable is snagged or the SAAFPU falls.

Figure 6: Connecting an SAAFPU to a PC - (A) serial-to-USB cable, (B) wireless adapter, and (C) front plate serial connection

Step 5 - Alternatively, Connect SAAFPU to PC Wirelessly  

The SAAFPU comes equipped with a 9-pin wireless adapter (Figure 6.B above) to be used with a computer with built-in Bluetooth. Connect the adapter to the serial connection on the front facing plate of the SAAFPU, Figure 6.C above. 

NOTE: Older models of the SAAFPU are equipped with a USB wireless adapter. If your computer has built-in Bluetooth, then a USB wireless adapter is not required to make a connection with the SAAFPU. Do not plug in the USB wireless adapter if your computer has built-in Bluetooth. 
NOTE: If you are using an older model of the SAAFPU that is equipped with a USB wireless adapter and your computer does not have built in Bluetooth, connect the adapter that is equipped with a USB plug to a PC. Microsoft operating systems from Windows 8 and beyond will automatically detect and install drivers for the wireless adapter. Older operating systems may require you to download drivers using Windows Update. When it is ready to use, a solid blue light will remain lit on the adapter.

Once the adapter is plugged in, click on your Start menu and select the Settings option.

Figure 7: The Settings option in the Start menu

In the Settings window, select the Bluetooth & other devices option. Enable the slider under Bluetooth and click the Add Bluetooth or device button.

Figure 8: The Bluetooth & other devices section of the Settings window

In the Add a device dialog, click the Bluetooth option. A listing of discovered Bluetooth devices will be displayed. The SAAFPU will be listed as FireFly-#### or SAAFPU-####, where #### is an alphanumeric identifier. Select the FireFly-#### or SAAFPU-#### option, enter the pin code 1234, and click the Connect button.

Figure 9: Add the FireFly-#### Bluetooth device and enter 1234 for the pin

NOTE: If you are using an older SAAFPU with the USB wireless adapter, the blue light in the USB adapter will blink until it successfully pairs with the 9-pin adapter plugged into the SAAFPU, at which point the blue light will remain solid on. Wait for the USB adapter to stop blinking and become solid. This indicates that the adapters have successfully paired. 

In the Bluetooth & other devices window, a device named FireFly-#### or SAAFPU-#### should appear under Other Devices with a status of paired.

Figure 10: FireFly-#### is listed as paired under Other devices when it is correctly configured

If pairing is unsuccessful, make sure that the 9-pin adapter is properly connected to the serial port on the SAAFPU and that there is nothing between the computer and the SAAFPU interfering with the wireless connection.

NOTE: Bluetooth wireless is a short range wireless technology. Your computer should remain close to the SAAFPU for proper communication

Step 6 - Start SAARecorder

Start SAARecorder. In SAASuite 3.0 or higher, the SAARecorder application is launched by clicking the Manual Data Collection button.

Figure 11: Launch SAARecorder from SAASuite by clicking the Manual Data Collection button

Click the Connect SAA button. 

Figure 12: The SAARecorder Startup window

In the Connect window, select the COM port you are using in the Serial Port(s) section. In the Connection to SAA section, select the SAA Field Power Unit option. If the SAAFPU is connected wirelessly to a PC, ensure the Wireless checkbox is checked. 


Figure 13: The SAARecorder Connect window

To go to the data collection portion of SAARecorder, click the Start with found SAAs button. Otherwise, click the Next button and follow the steps listed below.

Step 7 - Optional, Click on the Search Tab

Click on the Search tab in the Connect window of SAARecorder. This causes SAARecorder to look for ShapeArrays on each of the previously selected serial ports or SAA232-5 channels as described in the above mentioned guides. It tests communications with each microprocessor of a ShapeArray.


Figure 14: The Search tab in the SAARecorder Connect window

Each microprocessor has a unique serial number and is responsible for one item based on the model of ShapeArray connected: 
  • Models 1 and 2 SAAF and SAAScan: An octet (group of 8 segments) 
  • Model 3 SAAF and later S: A segment (every segment has a microprocessor) 

If the search is successful and the expected devices are found, click the Next button, as shown in the figure above. If any issues occur please refer to the Software FAQs.

Step 8 - Optional, Click on the Devices Tab

Some devices are not automatically detected. The Devices tab is where they would be added manually. Devices that have been previously found in the Connection or Search tab should appear here automatically. Some devices, such as piezometers and older ShapeArrays, need to be added manually. To add a device manually, click the Add Device link in the SAA Serial Numbers table.


Figure 15: The Devices tab in the SAARecorder Connect window

In the Enter Device Serial Number dialog, enter the Serial Number and COM Port and click the OK button. 


Figure 16: The Enter Device Serial Number dialog

Repeat this step until all desired devices have been added. Once all the devices have been selected click the Next button.

Step 9 - Optional, Click on the Test Tab

The Test tab runs Basic and Voltage / Current tests on the devices before starting SAARecorder application. Each test can be performed by clicking their respective buttons. Both tests can be performed if desired. The SAARecorder interface for viewing and recording data can be started by clicking the Continue button or clicking the Save and Continue button.


Figure 17: The Test tab in the SAARecorder Connect window

Step 10 - Disconnect From the PC

Close SAARecorder to power down the ShapeArray. If applicable, disconnect the SAAFPU USB cable from the PC. Disconnect the ShapeArray from the SAAFPU.

Step 11 - Optional, Troubleshoot Connection Issues

If there are issues connecting, please refer to the following FAQs