RC2500 Support Page


Cut Sheets
RC2500 Cutsheet

Manual
RC2500 Manual

AIU2 Cutsheet

AIU3 Cutsheet


Index
ACU
AIU

Resolvers (displaying stars)
Retrofit Information
FAQ
















Resolvers (displaying stars) back to top
If one of your axis are displaying stars, then this could indicate a bad connection. Whenever resolvers are not connected to the controller, the screen will display stars. Verify your connection to the controller and to the resolver.


Retrofit Information back to top

Retrofit Information back to top
When working with the RC2500 ACU/AIU System, there are several items that must be specified.

Limit Switches The RC2500 AIU requires limit switches that operate at each of the six limits AZ CW/CCW, EL UP/DOWN, and POL CW/CCW. A unique aspect of the RC2500 AIU is that it uses both a normally closed contact pair (NC, opens at limit), and a normally open contact pair (NO, closes at limit) at each limit. The NC contacts are used to interrupt the axis drive command and the NO contacts are used to provide a signal of the limit to the ACU and indicators on the AIU switch panel. Only 24VDC control loop signals are passed through the limit switches.
Common industrial limit switches have both NO and NC contacts that actuate at a given position. Traditional AIU’s have not used the NO contacts in the past. The use of all four contacts allows a simpler and easier to maintain AIU.
Wiring between the RC2500 AIU and each limit switch will be a 4-conductor cable such as RCI p/n CBL-4_22SHLDUV. An example of a standard industrial limit switch with both NO/NC contacts would be RCI p/n SW-ZCKJ404. Actuator arms for this switch can be ordered such as SW-ZCKY-11 (1.6 inch arm) or SW-ZCK-41 (1.57 to 3.35 inch adjustable arm). Often (depending upon the mechanical design) a single limit switch can provide both limits for a given axis. i.e. UP and DOWN for the EL axis in the same switch body.

Resolvers
The RC2500 ACU requires resolvers for position feedback. The resolvers should be mounted on the fundamental axis (AZ, EL, or POL) of the antenna. Some antennas use a resolver that is not on the fundamental POL axis but is still operated with a 1:1 gear ratio to that axis. The RC2500 is meant to operate with a specific resolver type, RCI p/n RSLVR11-2_1A (+ 7arc min accuracy), or RCI p/n RSLVR11-2_1B (+ 3arc min accuracy). Resolvers on the RC2500 system operate with a measurement precision of 0.0055 degrees. The display resolution of the RC2500 for AZ and EL is 0.01 degrees. RCI resolvers have 0.120” shafts.
The mechanical mounting of the resolvers is the responsibility of the integrator. RCI can provide some small resolver clamps and shafts couplers for this purpose. The following parts are available:
Z-RSLVR-SQ11, 0.93” resolver clamp; Z-CPL-C05-5, ¼” to 1/8” zero-backlash shaft adapter, Z-RSLVR-BOOT2, 4 inch x 1 inch resolver weather boot. Some Bracket kits are available to replace Harris/Vertex 90V Synchros: M-RSLVRBRKT-1 for Az or EL and M-RSLVRBRKT-2 for POL.
Resolvers require a 3x shielded-twisted pair cable connection to the ACU such as RCI p/n CBL-3x2_22STP1. This cable is best run directly from the ACU to the resolver itself. Optionally, it may be passed through, and / or, connected through a terminal block in the AIU. When making the resolver connections each of the shield connections (3, one for each pair) must be carried though at the AIU terminal block as an isolated connection. The shield must be connected to chassis ground at the ACU, and be open-circuited (and insulated) at the resolver itself. A useful way to run the resolvers may be to pull the three cables along with the Drive/limit cable in a common conduit from the ACU, then loop each individual cable immediately out of the AIU to the resolver without opening the cable jacket. The Resolver Cables terminate at the ACU with DB-9 Plugs.
Optionally, a potentiometer may be used to sense the polarization axis position only. Order option FC-2_5KPLP2. FC-2_5KPLP2 consists of a small circuit module that connects to the back of the RC2500. A cable containing a shielded triple runs from this module to the polarization-axis-mounted potentiometer.

Motors
The RC2500 AIU is designed to operate with single inverter-duty 3-phase AC Motors for the azimuth and elevation axes. When ordering the RC2500 AIU, the customer must specify the operating voltage and horsepower rating of each Motor to be used. Optionally, the customer may supply a manufacturer and manufacturer part number for these two motors to RCI at the time of order. The standard RC2500 AIU operates with 3HP and smaller motors. The use of a particular motor type may put limitations on the required pad power. Heavy-gauge, high-voltage rated cable is recommended for the motor connections such as RCI p/n CBL-4_16SHLDDR.
The RC2500 AIU is designed to operate with a single-speed, single-phase, fractional horsepower, reversing AC motor for polarization. The customer must specify the manufacturer and manufacturer’s part number for this motor to allow RCI to determine the correct motor-starting components to be used.
Optionally, the customer may use a 24V DC low-current motor for polarization control. Please specify motor manufacturer and manufacturer part number at the time of order.

Antenna-Component connections
Three, ½ - inch, liquid-tight conduit fittings are provided on the bottom of the AIU for connection to the conduit run to each limit switch. This assumes that three switch units are used, combining the two limits for each axis. Additional holes must be drilled in the AIU housing if separate limit switches are used on a given axis.
An additional three, ½-inch liquid-tight conduit fittings are provided on the bottom of the AIU to run the resolver connections.
½ inch liquid tight conduit, (RCI p/n CDT-M-0_5 LQT), straight conduit connectors (RCI p/n CN-GY-4Q50), 45 degree conduit connectors, (RCI p/n CN-GY-4Q450), and 90 degree conduit connectors, (RCI p/n CN-GY-4Q950) are available for these conduit runs described above. Optionally, liquid-tight cable fittings (RCI p/n LQT-3217 for 0.17” to 0.45” diameter cable, or LQT-3220 for 0.23” to 0.53” cable) may be used. If you elect to run cabling without conduit, be sure to use a UV and weather resistant outer jacket for a long installation life. Conduit clamps or UV-resistant nylon zip-ties (RCI p/n NY-C-TIE 11_25, 11.25” UV resistant; or RCI p/n NY-C-TIE 33”, 33” UV resistant) may be used to secure the conduit/cable run to the antenna structure.
Due to the high voltages used in operating the motors, conduit should be used for these runs. Three, ½-inch liquid-tight conduit fittings are provided on the bottom of the AIU to run the motor connections for Azimuth, Elevation, and Polarization.
Due to the many possible configurations/uses of the RC2500 AIU, Cable, Conduit, and Conduit fittings should be ordered separately.

ACU to AIU Connections
In addition to the three resolver cables mentioned above, the drive/limit connections between the RC2500 ACU and the RC2500 AIU are carried in a single run of 25-conductor shielded cable, RCI p/n CBL-25_22. 23 conductors are required to implement the basic ACU to AIU Drive/Limit interface. These four cables may be run in the same conduit. A single 1-inch conduit fitting is placed in the bottom of the AIU for this purpose.
The 25-conductor cable terminates at the ACU in two DB-25 connectors, one plug and one receptacle. The three resolver cables each terminate at the ACU in a DB-9 plug. Mating connectors are supplied with the RC2500 ACU.

Pad Power
AC power with a local disconnect must be supplied to the AIU for operation. The required pad power (current and voltage) will be determined by the choice of motors used. It is recommended that the service be sized to between 2 times and 2.5 times the sum of the maximum full-load current for all axes operating simultaneously.

RC2500 ACU
The RC2500ACU may be ordered with or without the capability to track inclined orbit satellites. The RC2500B has that option, the RC2500A does not. All RC2500 ACUs have an RS-422 M&C interface, standard.
There are more than 25 variations of the RC2500 hardware/software configuration. When operated with a standard RC2500 AIU, an “RC2500 ; std i/o” should be ordered.
When ordering an RC2500 product, please specify the operating voltage. This is switchable at the back panel and will be pre-configured per the purchase order.
Specify the Satellite list to be used. There are three satellite lists which vary by satellite longitude, WEST (from the central Pacific to the central Atlantic); EAST (from the central Atlantic to the Middle East); and ASIA PACIFIC (from the Middle East to the Central Pacific). Satellite lists are updated every year, on average. Any satellite list can contain out-of-date information. New or Modified Satellite information can be entered into the ACU using the USER satellite.
If the Polarization Potentiometer option is ordered, it must be specified as a separate line item (FC-2_5KPLP2) on the PO at time of order.