Mount the PwrPak7-E1
This section applies to all PwrPak7 enclosures with an integrated IMU (i.e. PwrPak7-E1, PwrPak7D-E1, PwrPak7-E2 and PwrPak7D-E2). Anywhere PwrPak7-E1 is used in this section, it is referring to any of these receivers.
Mount the PwrPak7-E1 in a fixed location where the distance from the receiver to the GNSS antenna phase center is constant. Ensure that the orientation with respect to the vehicle and antenna is also constant. Secure the PwrPak7-E1 using four M5 or #10 size screws fastened through the PwrPak7-E1 mounting holes. The torque rate of the screw should not exceed 15 inch-lb. See PwrPak7 Mechanical Specifications for drawings of the PwrPak7-E1 dimensions and locations of the mounting holes.
For attitude output to be meaningful, the PwrPak7-E1 should be mounted such that the positive Z-axis marked on the receiver points up and the Y-axis points forward through the front of the vehicle, in the direction of track. If the PwrPak7-E1 is not mounted in this orientation, a rotational offset must be applied. See
Also, it is important to measure the distance from the PwrPak7-E1 center of navigation to the antenna phase center (the Antenna Lever Arm) on the axis defined on the PwrPak7-E1. For the PwrPak7D-E1 and PwrPak7D-E2, the lever arm to both the primary and secondary antenna must be measured. See
The enclosure axis labels are approximately located at the center of navigation. For precise offsets from the enclosure reference point to the IMU center of navigation, use the information located on the label on the bottom of the enclosure.
Ensure the PwrPak7-E1 cannot move due to dynamics and that the distance and relative direction between the antenna and the PwrPak7-E1 is fixed.
The closer the antenna is to the PwrPak7-E1, particularly in the horizontal plane, the more accurate the position solution. Also, the measurements entered using the SETINSTRANSLATION command must be as accurate as possible, or at least more accurate than the GNSS positions being used. For example, a 10 cm error in recording the antenna offset will result in at least a 10 cm error in the output. Millimetre accuracy is preferred.
The offset from the PwrPak7-E1 to the antenna, and/or a user point device, must remain constant especially for RTK or DGNSS data. Ensure the PwrPak7-E1, antenna and user point device are bolted in one position perhaps by using a custom bracket.
Wi-Fi Interface
The Wi-Fi interface SSID and default security key are printed on a label on the bottom of the PwrPak7-E1. If you intend to use the Wi-Fi interface and NovAtel Web User Interface, record the SSID and default security key before securing the PwrPak7-E1 in its mounting location.