AccuGrade GPS (CD700) System Components Caterpillar

System Components
1.1. Guidance Information
2.2. Display
3.3. Slot for the Data Card
4.1. Sensors
5.2. Angle Sensors
6.2. 3D Sensors
7.3. GPS/GNSS Receiver
8.1. Other Components
9.2. Data Radio
10.1. Base Station

The main component of the AccuGrade System is the display. The display is used in order to display the guidance information to the operator of the machine. In addition to the display, there are a number of sensors that are used with the system.

The display, and the various sensors are connected electrically by a system harness that allows the system components to send data and commands between each other.

Additionally, the AccuGrade System requires one of the following types of base stations somewhere near the project:

  • Global Positioning System (GPS)

  • Global Navigation Satellite System (GNSS)

Guidance Information

Guidance is given to the operator in the following way:

  • CD700 Display


Illustration 1g01265962

(1) LCD

(2) Soft Key Labels

(3) Soft Keys

(4) Escape Key

(5 ) Next Key

(6) Power Key

(7) "+" Key

(8) Arrow Keys

(9) "-" Key

(10) "OK" Key

(11) Menu Key

(12) "Data Card Slot"

The display is a computer that runs the software for the AccuGrade System. The display has a LCD screen in order to display guidance information and other information. The display has push buttons that are used to operate the AccuGrade System.

Slot for the Data Card

Illustration 2g01265965

(12) "Data Card Slot"

The display has a slot for a data card that is used for loading and saving the machine data and the configuration data for the display. The data card is also used for loading and saving designs.


The guidance information that is provided by the system depends on the following:

  • Type of sensors

  • Number of sensors

AccuGrade can operate with the following types of sensors:

Angle Sensors

Illustration 3g01417327

The AS400C angle sensor (14) is a highly accurate sensor that is capable of measuring up to +/- 45 degree slopes. The sensor is used to measure the mainfall (pitch) of the machine.

The AS400C angle sensor is mounted on the bowl. The angle sensor measures the cross slope of the cutting edge of the bowl.

3D Sensors

The sensors that are used by the AccuGrade System allow the AccuGrade System to determine the location of the machine in three dimensional space. The following location sensors are used by the AccuGrade System:

  • GPS Receiver

GPS/GNSS Receiver

Illustration 4g01417316

(27) GPS Receiver

(28) Mast

(29) Thumb Wheel On Quick Release Bracket

The sensors that are used by the AccuGrade System allow the AccuGrade System to determine the location of the machine in three dimensional space. The following GPS receivers are used:

  • MS980C Receiver

  • MS990C Receiver

Both receivers are able to calculate the positions by using information that is broadcast from the GPS satellites that are orbiting the earth and correction signals that are sent from a base station. The MS990C receivers will also use information that is broadcast from the GNSS satellites if a GNSS base station is used.

Other Components

The following components may also be connected to the system.

Data Radio

Illustration 5g01428755

A data radio is used in order to receive data from one of the following types of base stations:

  • GPS

  • GNSS

The data radio is required to be working before the system can be used. The GPS data radio can also be used in order to send and receive files and other types of data from the office.

The CR radio supports the following frequencies.

  • 450 MHz Data Radio

  • 900 MHz Data Radio

  • 2.4 GHz

The CR radio can support two of the frequencies that are listed above with the same radio.

Base Station

Note: One of the following types of base station is required for the AccuGrade System to function correctly:

  • GPS

  • GNSS

Currently, AVSpare does not support GPS Base Stations. A Base Station from Trimble is recommended.

A base station consists of the following components:

  • GPS Receiver or GNSS Receiver

  • GPS Antenna or GNSS Antenna

  • Radio

  • Cables

  • Power Supply

There may also be a tripod or a mast for the antenna and the radio. For construction sites when work can continue for a long time, use a semi-permanent location such as the roof of the site office. A reliable power supply is needed.

Make sure that the base antenna is clear of obstructions, reflected signals, and sources of electromagnetic interference such as power lines.

The data radio for the base station must be elevated several meters off of the ground in order to provide optimum coverage.

The base station requires a starting location. For best results set up the receiver for the base station on a surveyed point. In order to establish this survey point, use a site calibration or a professional surveyor experienced with this type of equipment.

You must correctly set the antenna type at your base station. The position is degraded if the incorrect type of antenna is selected.