Rs485 Serial Port; Defaults - GE 239 Instruction Manual

4.2.3

RS485 Serial Port

4.2.4

Defaults

4–16
Courtesy of NationalSwitchgear.com
accordingly. The analog output can be connected to a remote meter, which is
available and calibrated from 0 to 100% of motor capacity used. Select thermal
capacity 0-1 MA (0 mA = 0%, 1 mA = 100% i.e. motor tripped) for use with the 0-1 mA
range meter model TCS2 scaled in units of thermal capacity used and available from
GE Multilin. This meter would be situated near the operator and connected to the
relay. The meter indicates how much the memory has charged corresponding to heat
buildup in the motor. When the relay is about to trip, the meter will approach 100%
capacity used. After a trip, the meter will indicate how much charge is left in the
memory to give a rough idea of the lockout time remaining. Alternately, this output
can be programmed as thermal capacity
motor tripped) and connected to a programmable controller or DCS as a signal for
process control. It might typically be used to reduce the feed on to a conveyor as the
conveyor motor thermal capacity approached 100%.
• SERIAL COMMS FAILURE ALARM: If loss of communications to the external master is
required to activate the alarm relay, select ON. In this case an absence of
communication polling on the RS485 communication port for 60 seconds will
generate the alarm condition. Disable this alarm output if communications is not used
or is not considered critical.
• SLAVE ADDRESS: Enter a unique address from 1 to 255 for this particular relay on the
RS485 communication link. This setpoint cannot be changed via the RS485 port. A
message sent with address 0 is a broadcast message to which all relays will listen but
not respond. Although addresses do not have to be sequential, no two relays can have
the same address or there will be conflicts resulting in errors. Generally, each relay
added to the link will use the next higher address, starting from address 1.
• BAUD RATE: Enter the baud rate for the terminal RS485 communication port, which may
be selected to one of 1200
communication link and the computer connecting them must run at the same baud
rate. The fastest response will be obtained at 19200 baud. Slower baud rates should be
used if noise becomes a problem. The data frame consists of 1 start bit, 8 data bits, 1
stop bit and a programmable parity bit, see
The baud rate default setting is 9600 baud.
• PARITY: Enter the parity for the terminal RS485 communication port, which may be
selected to one of EVEN ,
and the computer connecting them must have the same parity.
• LOAD FACTORY DEFAULTS: When the 239 is shipped from the factory all setpoints will
be set to factory default values. These settings are shown in the setpoint message
reference figures. To return a relay to these known setpoints select
key while this message is displayed and then momentarily remove power
STORE
to the 239. It is a good idea to first load factory defaults when replacing a 239 to
ensure all the settings are defaulted to reasonable values.
(4 mA = 0%, 20 mA = 100% i.e.
4-20 MA
, 2400 , 4800 , 9600 , or 19200 baud. All relays on the RS485
S1: 239 SETUP\RS485 SERIAL PORT\PARITY
ODD , or NONE . All relays on the RS485 communication link
239 MOTOR PROTECTION RELAY – INSTRUCTION MANUAL
CHAPTER 4: PROGRAMMING
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YES and press the