Section 3. ET Instrumentation Installation

3)Connect the 5-foot patch cord to the Rad Modem. Fasten the cable to the strain relief tab with a cable tie. Connect the Rad to the PC's serial port either directly (25 pin port) or through a 9 to 25 pin serial converter.

4)Route the user-supplied cable from the remote splice to the surge protector. Connect it and the 5-foot patch cord to the surge protector.

ET106 ENCLOSURE

PC

SRM-5A

+ RCV (red)

- RCV (black)

+ XMT (green)

- XMT (white)

- RCV (white)

+ RCV (green)

QC

- XMT (black)

- S/N E1055

+ XMT (red)

SC932

 

+RCV (red)

-RCV (black)

+XMT (green)

-XMT (white)

To # 8

External Connector

Surge

 

 

Splices

Protector

 

User

 

 

Supplied

1

 

 

+ RCV

 

1

Cable

RED

 

 

2

 

2

 

 

 

- RCV

 

 

 

BLACK

 

3

 

3

 

 

 

 

 

 

+ XMT

 

4

 

GREEN

 

 

 

4

 

 

 

- XMT

WHITE

ENCLOSURE ET106

Earth Ground

FIGURE 3.3-5. Short-Haul Modem Wiring Diagram

3.4 Sealing and Desiccating the Enclosure

The ET Enclosure is supplied with a desiccant pack. The desiccant maintains a low humidity in the enclosure to minimize the chance of condensation on the instrumentation. Desiccant should be changed when the internal ET Enclosure humidity sensor measures 30% or higher. Install the desiccant as shown in Figure 3.4-1. Keep unused desiccant tightly sealed in an airtight container.

1)Take the desiccant pack out of its sealed plastic bag. Place it under the desiccant strap just before leaving the station.

2)Be sure to close the enclosure hasp securely. A padlock may be used on the latch for extra security.

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