Speed Switch Terminals; Programming Access Terminals; Rs485 Serial Communications Terminals - GE 269Plus Instruction Manual

Motor management relay
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SPEED SWITCH TERMINALS

Terminals 50 and 51 are provided for connection to an external speed switch. This allows the 269Plus relay to
utilize a speed device for locked rotor protection. During a motor start attempt if no contact closure between
Terminals 50 and 51 occurs within the
relay assigned to the speed switch function will activate. This function must be enabled in order for operation to
occur. After a SPEED SWITCH TRIP, Terminals 50 and 51 must be open circuited in order to reset the relay.
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If no speed switch is to be used terminals 50 and 51 should be left open. A twisted pair of wires should be
used. Connection to the 269Plus is made via a terminal block which can accommodate up to #16 AWG multi-
strand wire.
Do not connect live circuits. Dry contacts connections only.
CAUTION
When a jumper wire is connected between ACCESS terminals 52 and 53 all setpoints and configurations can
be programmed using the keypad. Once programming is complete the jumper will normally be removed from
these terminals. When this is done all actual and setpoint values can still be accessed for viewing; however, if
an attempt is made to store a new setpoint value the message "ILLEGAL ACCESS" will appear on the display
and the previous setpoint will remain intact. In this way all of the programmed setpoints will remain secure and
tamperproof. Alternatively, these terminals can be wired to an external keyswitch to permit setpoint program-
ming upon closure of the switch. For additional tamper proof protection, a software access code may be pro-
grammed on Setpoints page 6. See Section a): STARTS/HOUR TIMER on page 3–15 for further details.
A twisted pair of wires should be used for connection to an external switch. Connection to the 269Plus is made
via a terminal block which can accommodate up to #16 AWG multi-strand wire.
Terminals 46 and 47 are provided for a digital serial communication link with other 269Plus relays, computers,
or programmable controllers. Up to 32 269Plus "slaves" can be connected to one "master" (PC/DCS/PLC) as
shown in Figure 2–15: SERIAL COMMUNICATION LINK WIRING on page 2–23. The GE Power Management
269 Plus Relay Communication Protocol (Modbus RTU Compatible Protocol) is described in Chapter 4:COM-
MUNICATIONS. Note that when using a 269Plus slave, setpoints sent to the slave must be within the ranges
listed in Table 3–3: 269Plus SETPOINTS on page 3–18.
Each communication link must have only one master. The master should be centrally located and can be used
to view Actual Values and Setpoints from each relay slave. Setpoints in each slave can also be changed from
the MASTER. Each SLAVE in the communication link must be programmed with a different slave address.
To avoid contention and improper reading of data ensure that the following conditions are met:
1. Each communication link has only one master.
2. Each 269Plus slave in the link has a different slave address.
The wires joining relays in the communication link should be a shielded twisted pair (typically 24AWG). These
wires should be routed away from high power AC lines and other sources of electrical noise. The total length of
the communications link should not exceed 4000 feet using 24AWG shielded twisted pair. When connecting
units in a communication link, each 269Plus relay must have Terminal 47 connected to Terminal 47 of the next
unit in the link, and Terminal 46 connected to Terminal 46.
As shown in Figure 2–15: SERIAL COMMUNICATION LINK WIRING on page 2–23, the first and last devices
in the link should have a terminating resistor and capacitor placed across Terminals 46 and 47. The value of
this R-C network is typically a 120 Ω terminating resistor in series with a 1 nF capacitor.
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Courtesy of NationalSwitchgear.com
S P E E D S W I T C H T I M E D E L A Y

2.17 PROGRAMMING ACCESS TERMINALS

2.18 RS485 SERIAL COMMUNICATIONS TERMINALS

269Plus Motor Management Relay
2 INSTALLATION
2.16 SPEED SWITCH TERMINALS
setpoint (see Setpoints page 5) the output
GE Power Management

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