Patton electronic 1012B user manual How To Connect To The Twisted Pair Interface, Installation

3.2 SETTING THE RTS/CD CARRIER CONTROL JUMPER

The RTS/CD jumper (see Figure 1) is identified as J2 inside the

1012B (see Figure 1). To access this strap, do the following:

1.Using a small screwdriver, insert the tip into one of the slots in the side of the Model 1012B (see Figure 2).

2.Rotate the screwdriver as shown in Figure 2 to open the case.

DTE/DCE Switch Setting	DCE (Default)	DTE
RTS/CD jumper in place	Carrier activated by	Carrier activated by
(default)	RTS - pin 4 (default)	CD - pin 8
RTS/CD jumper removed	Carrier constantly ON	Carrier constantly ON

Table 1. Interaction of DTE/DCE switch and RTS/CD strap

3.The RTS/CD carrier control jumper setting on the 1012B determines whether the transmitter is constantly on or is controlled by an RS-232 control signal. When this jumper is removed from the pegs, the 1012B transmitter is constantly on. When the jumper is in place on the pegs, the transmitter is controlled by either RTS or CD. When the control signal is a positive voltage, the transmitter is turned on, if negative voltage, the transmitter is off. See Table 1 for the correspondence between DTE/DCE and RTS/CD parameters.

DTE/DCE Switch Setting	DCE	DTE
Carrier Detect Function	Carrier detect is output	Carrier detect is output
	on pin 8 (CD)	on pin 4 (RTS)

Table 2. Interaction of DTE/DCE switch and RTS/CD jumper

4.The RTS/CD carrier control jumper also controls which signal will function as the Carrier Detect (CD) signal. If the DTE/DCE switch is set to “DCE,” the carrier detect is output on Pin 8. If the DTE/DCE switch is set to “DTE,” the carrier detect is output on Pin 4. Table 2 shows which control signal provides the carrier detect function, per the DTE/DCE setting.

Note: For multi-point applications, it is necessary to have a jumper in place on the pegs on the slave modems.

5.After you finish configuring the DTE/DCE switch, snap the case halves back together and continue the installation process.

4.0 INSTALLATION

Once you have properly configured the Model 1012B, you are ready to connect it to your system. This section tells you how to connect the Model 1012B to the twisted pair and RS-232 interfaces, and how to operate the Model 1012B.

4.1 HOW TO CONNECT TO THE TWISTED PAIR INTERFACE

The Model 1012B passes data and handshaking signals between two RS-232 devices at distances to 6 miles (9.7 km) and data rates to

38.4kbps. There are two requirements for installing the Model 1012B.

1.These units work in pairs. Therefore, you must have one Model 1012B at each end of a two twisted pair interfaces.

2.To function properly, the Model 1012B needs two twisted pair of metallic wire. They must be unconditioned, dry metallic wire, unloaded, between AWG 19 and 26 (the higher number gauges may limit distance somewhat). Standard dial-up telephone circuits, or leased circuits that run through signal equalization equipment, are not acceptable.

For your convenience, the Model 1012B is available with the following twisted pair interfaces: RJ-11 jack, RJ-45 jack, and terminal blocks.

4.1.1 TERMINAL BLOCK TWISTED PAIR CONNECTION

If your application requires you to connect one or two pair of bare wires to the Model 1012B, you will need to access the external terminal blocks. The following instructions will tell you how to connect the bare wires to the terminal blocks.

1.Strip the outer insulation from the twisted pairs about one inch from the end.

2.Strip the insulation on each of the twisted pair wires about 0.25 inch.

Figure 4. Stripping the outer insulation from the twisted pairs

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