Wavetronix VDR24 Radar - Manual (Page 34)

Installing the VDR24 Controller
34 VDR24 Radar Detection System, Rev 1.0
Connect each of the seven conductors of the home run cable from each of the radar sensors
(Radar 1 and Radar 2) to the appropriate terminal using the following color-coding legend:
TTaabbllee 66 -- R Raaddaarr C Caabbllee C Coolloorr C Cooddiinngg
Terminal
Position
Label Description Wire and Label Color
Legend
1
PWR
PWR +
Isolated +24VDC Power to Radar Sensors Solid Red
2
PWR
GND -
Isolated DC Power Ground to Radar Sensors Solid Black
3
CONTROL
485+
RS-485+ Radar Control Line Blue with White Stripe
4
CONTROL
485-
RS-485- Radar Control Line Solid Blue
5
DATA
485+
RS-485+ Radar Data Line Orange with White Stripe
6
DATA
485-
RS-485- Radar Data Line Solid Orange
7
SHIELD
DRN
Cable shield for noise suppression Bare Wire
5.3. Connecting Railroad Signals to the Controller
The VDR24 requires information from the crossing environment for full operation – specifically
the Crossing Relay (XR) and the Island Relay (IR). The connection procedure and rationale are
provided below.
5.3.1. Crossing Relay Connections
In order to focus attention on actual crossing activation periods (in vehicle detection at crossings
application), the VDR24 wants to know when to expect a train. In some applications, this signal -
- called the crossing relay or XR - is used to activate video recordings. The XR+ and XR- inputs
on the left side of the VDR24 drive an opto-isolated input to signal the XR state to the VDR24.
Battery should connect through the separate contacts of the railroad’s XR relay, through XR+
and from XR- to Battery ground.
FFiigguurree 1155 -- TTyyppiiccaall XXR R aanndd IIR R C Coonnnneeccttiioonnss
+
_
XR and IR Relay Contacts
Normally Open
VDR24 + and – inputs for
XR and IR
+12V Battery Supply
B12
Battery Supply Ground
N12