Siemens IGWIPS200-1 - Manual (Page 12)

IGWiPS200-1
ANTENNA CONNECTORS AND SURGE VOLTAGE PROTECTION
Each transceiver has an MCX female antenna connector. The base 3-1/2", 1/4-wave whip antenna has an MCX male
connector. Optional higher gain antennas and low-loss coaxial cables have type-N connectors. MCX to type-N
adapters and other connector adapters are available. Optional antennas may be accompanied by additional
installation instructions.
If an antenna will be installed out-of-doors or otherwise exposed to surge voltages or strong electromagnetic fields,
such as from a nearby lightning strike, a COAXTRAB Surge Voltage Protection Adapter should be included in the
installation; see Figure 1 for a typical installation. The adapter features a user replaceable gas arrestor tube that
shunts induced high voltage to ground to help protect the transceiver.
Type-N connectors are provided on the adapter; the genders of the two adapter connectors are specified by the
adapter part number. Mount the surge adapter through a bulkhead, through the wall of an enclosure (as shown in
Figure 1), in-line with the antenna cable, on the supplied straight bracket, or on a user-fabricated bracket. Installation
instructions are supplied with the adapter.
CURRENT (AMPERAGE) BUDGET CALCULATION
A common current bus interconnects a transceiver and its connected I/O modules; see Figure 2. The current on this
bus may not exceed 5A. This section shows how to calculate the current flowing on the common current bus. Note
that the calculations in this section are also useful when determining power supply requirements at each transceiver
location.
Figure 2 shows a two-node (remote site and control room) wireless network. The remote site has a remote
transceiver, two input modules, and a power supply. The master transceiver is installed at a control room with two
complementary output modules and a power supply.
The bus current at each transceiver location is calculated by summing the current requirements for the transceiver
and all connected I/O modules. Table 2 lists the current requirements of each module type.
Remote Site Control Room
Common
Current Bus Common
Current Bus
Remote Transceiver
Analog Input Module,
Address 1
Digital Input Module,
Address 2
Power Supply
Master Transceiver
Analog Output Module,
Address 1
Digital Output Module,
Address 2
Power Supply
MG
0
043
0a
Figure 2 Current (Amperage) Budget Example
Remote Site
As shown in Figure 2, the remote site has one remote transceiver, one analog input module, and one digital input
module. Table 2 shows that the transceiver draws 75 mA, the digital input module 26 mA, and the analog input
module 32 mA plus 20 mA per active channel. The total current (I
t
) requirement is:
I
t
= 75 mA + 26 mA + 32 mA + (4 x 20 mA) = 213 mA
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