Research Concepts RC2500 - Manual (Page 20)

RC2500 Antenna Controller Chapter 3 Installation/Setup 13
Research Concepts, Inc. • 5420 Martindale Road • Shawnee, Kansas • 66218-9680 • USA www.researchconcepts.com
3.3.1.3 Resolver Electrical Connections
NOTE: SHIELDED CABLE IS REQUIRED FOR THE RESOLVER CONNECTIONS. THE
SHIELD MUST BE CONNECTED TO RC2500 CHASSIS GROUND AT THE CONTROLLER
AND MUST NOT BE CONNECTED AT THE ANTENNA.
Three shielded twisted-pairs for each resolver are required to minimize noise pickup and cross-coupling,
which can result in antenna positioning errors. A cable such as Belden 87777 (RCI p/n CBL-
3x2x22_STP) is recommended. Most resolvers have flying lead connections. Wire-to-wire interconnects
can be accomplished with solder and heat shrink tubing or a water-proof crimp connector such as RCI
p/n CN-JIZR.
J2, J3, and J4 are identical DB-9 receptacles The duplicated pinout of these connectors allow for easy
testing of the position sensing circuitry by swapping connectors. The individual pin definitions are as
follows:
Pin # Description Resolver Wire Lead Color
1 Ref. Drain Wire No Connect at Resolver
2 Resolver Reference Red w/ White Stripe
3 Resolver SIN - Blue
4 Resolver COS - Black
5 Resolver SIN + Yellow
6 COS Drain Wire No Connect at Resolver
7 SIN Drain Wire No Connect at Resolver
8 Resolver Reference Yellow w/ White Stripe
9 Resolver COS + Red
The resolver type position sensors wired as in the table above should result in the sensed position
changing in the correct manner when the antenna is moved. The A.I.U. should already have been wired
such that the axes are all moving in the correct direction with local jog controls if any.
Here is the ‘correct’ relationship between antenna movement and sensed position.
• Azimuth CW antenna movement (as viewed by an observer located above the antenna)
must result in an increasing sensed position.
• Elevation UP antenna movement must result in an increasing sensed position.
• When the controller’s POL CW key is depressed, the sensed polarization position must
increase.
The LCD display of the RC2500 may show limit indications rather than the digitized angles. Proper
display of the sensed angles will not be possible until all of the antenna position limit connections are
accounted for.
3.3.2 Antenna Interface Connections
The RC2500 is designed to operate with an Antenna Interface Unit (A.I.U.) sometimes referred to as an
“outdoor box”. The A.I.U. contains the drive modules or contactors that switch power to the motors of the
antenna mount. It also supports wiring from antenna mounted limit switches which, when actuated, shut
down the motor drive for that axis/direction combination. Often the A.I.U. will have local jog controls that
allow service personnel to move the antenna at the pedestal. An emergency disconnect should always
be provided at the antenna pad for operating safety. This function may also be integrated into the A.I.U.