Cabletron Systems 2H253-25R manual Straight Cable Connection

Connecting to the Network

LED MODE Switch in RX–TX position

Receive (RX)

LED

MODE

RX-TX

	Transmit (TX)
DPX-SPD

			SWITCH
FAST	ETHERNET		WORKGROUP
			LED
			MODE
			RX-TX
			DPX-SPD
			PWR
			CPU
			RESET
2H253		-25R	COM

									20	22	24
								18			23
							16			21
						14			19
					12			17
				10			15
			8			13
		6
	4				11
				9
2			7
		5
	3
1

Screw

LED MODE Switch RJ21

Screw

2762-07

Figure 3-6 Straight Cable Connection

3.Tighten the two screws on the RJ21 straight cable connector to secure it to the device.

NOTE

The cable pinouts for a 25-pair cable (RJ21) can be found in the Cabletron Systems Cabling Guide. Refer to Section 1.2 for details on how to obtain this document.

4.Verify that a link exists on each twisted pair segment of the RJ21 connector by checking that the associated port RX LED is on (flashing amber, blinking green, or solid green). If the RX LED is off and the TX LED is not blinking amber, perform the following steps until it is on:

a.Verify that the LED switch located near the COM port of the device is in the left-most position (RX and TX LED indicators) as shown in Figure 3-6.

b.Verify that the UTP cabling used is Category 3 (for 10BASE-T) or Category 5 (for 10BASE-T or 100BASE-TX). The Category 5 cabling must have an impedance of between 85 and 111 ohms.

NOTE

If a port is to operate at 10 and 100 Mbps, Category 5 cabling must be used. Refer to Section 2.3 for information about 100BASE-TX networks and cabling.

Installation 3-9