GE 239 Instruction Manual page 43

4 PROGRAMMING
• DEFAULT MESSAGE BRIGHTNESS: The brightness of the displayed messages can be varied
with this setpoint. The brightness set by this setpoint will be used when the default messages are
being displayed. The brightness defaults back to 100% when:
• trip is present
• alarm is present
• any one of the keys on the 239 keypad is pressed
• the 239 is turned off and on
When 6  6(783?35()(5(1&(6?'()$8/7 0(66$*( 7,0( is set to 2)) , the brightness will adjust to
set level after 5 minutes have elapsed since the 239 keys were last pressed. The 239 status
must also be NORMAL to display the set brightness. If no default message is programmed, the
display brightness will adjust to the set level after the programmed time in message 6 
6(783?35()(5(1&(6?'()$8/7 0(66$*( 7,0( has elapsed.
NOTE: Message brightness control is available only with the VFD display option.
• BLOCK KEYPAD TRIP RESETS: This feature blocks any attempts made to reset the present
trip using the RESET key on the 239 keypad. When this feature is enabled and a trip is present,
pressing the RESET key will display the following flash message for 3 seconds.
This feature is applicable to trips only. The function of the
alarms, remove default messages, etc.) is not affected.
• OVERLOAD PICKUP DISPLAY ENABLE: When an overload pickup has occurred, this setpoint
determines whether the 239 front display panel is automatically updated with the time to overload
trip. When this setpoint is programmed to 12 , an overload pickup will have no effect on the dis-
play. The pickup LED indicator and overload protection are not affected by this setpoint.
b) ANALOG OUTPUT
• ANALOG OUTPUT TYPE: If the relay is to be used in conjunction with programmable control-
lers, automated equipment, or a chart recorder the analog output can be used for continuous
monitoring. Choose from one of the following parameters for output: 7+(50$/ &$3$&,7< , $9(5$*(
3+$6( $036 , 02725 /2$' (phase current as a percentage of full load), or 57' 7(03(5$785( .
Although a single parameter can be selected for continuous analog output, all values are avail-
able digitally through the communications interface. See Section 2.3h) ANALOG OUTPUT
(OPTION) (18/19/20) on page 2–11 for a description of current output scaling. Applications
include using a computer to automatically shed loads as the motor current increases by monitor-
ing current as a percentage of full load current or a chart recorder to plot the loading of a motor in
a particular process.
• ANALOG OUTPUT RANGE: In processes where the motor loads are varied and operated at
near the motor full load such as in grinding or in conveyor systems it is useful to know how close
the relay is to tripping so the load may be adjusted accordingly. The analog output can be con-
nected to a remote meter, which is available and calibrated from 0 to 100% of motor capacity
used. Select thermal capacity  0$ (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
GE Multilin
Courtesy of NationalSwitchgear.com
RESET NOT POSSIBLE
KEYPAD RESET BLOCKED
239 Motor Protection Relay
4 PROGRAMMING
key in other areas (i.e. reset
RESET
4
4-5