Operation overview, A419 control front-panel, Liquid crystal display – Johnson Controls A419 Series User Manual

Page 3: Output relay status indicator led, A419 control definitions, A419 functions set at the front-panel

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A419 Series Electronic Temperature Controls with Display and NEMA 1 or NEMA 4X Watertight Enclosures

Product/Technical Bulletin 3

Figure 4: A419 Temperature Control with NEMA 4X

Enclosure and A99 Temperature Sensor

Operation Overview

The A419 control’s front-panel, LCD, LED, and the
A419 control functions are described below. See the
Adjustments section for instructions on setting up and
adjusting the A419 control.

A419 Control Front-Panel

The front panel of the A419 control has a three-button
touchpad and LCD for adjusting control function
values, and an LED indicator that displays the On/Off
status of the SPDT output relay. See Figure 5.

MENU

F

BIN

MENU Button

DOWN Arrow

Button

UP Arrow

Button

Output Relay

Status Indicator

LED

Operating Mode

Indicator

Temperature

Units Indicator

Temperature

Offset Indicator

Liquid Crystal

Display

Figure 5: A419 Control Front-Panel with Display

Liquid Crystal Display

During normal operation, the LCD displays the
temperature at the sensor, the units of temperature
F or °C), and an icon indicating if the control is set for
Heating ( ) or Cooling ( ) mode. The LCD also
displays BIN if the Temperature Offset function is
activated. See Figure 5.

During control set up or adjustment, the LCD displays
the control functions and their values (settings). After
30 seconds of inactivity, the display returns to the
sensed-temperature display. See the Adjustments
section to adjust the control setting.

Output Relay Status Indicator LED

A green LED on the control’s front panel illuminates
when the SPDT output relay is energized and the
Normally Open (N.O.) contacts are closed.
See Figure 5.

A419 Control Definitions

Cut-in is the temperature at which the N.O. contacts
on the SPDT output relay close.

Cutout is the temperature at which the N.O contacts
on the SPDT output relay open.

A419 Functions Set at the Front-Panel

Setpoint (SP) establishes the temperature value that
energizes or de-energizes the output relay, depending on
the user selected mode of operation. The control may be
set either to cut in or to cut out at Setpoint. See the
Cooling/Heating and Setpoint Modes. The Setpoint range
is -30 to 212°F (-34 to 100°C).

If Setpoint mode is Cut-in, Setpoint is the temperature
value that closes the N.O. contacts. If Setpoint mode is
Cutout, Setpoint is the temperature value that opens
the N.O. contacts. See Figure 7 and Figure 8.

Differential (dIF) establishes the difference in
temperature (in F° or C°) between the cut-in and
cutout values. The differential is set relative to Setpoint
and may be set from 1 to 30F° or C°. See Figure 7 and
Figure 8.

Anti-Short Cycle Delay (ASd) establishes the
minimum time that the N.O. contacts remains open (after
reaching cutout) before closing again. The delay overrides
any Load Demand and does not allow the N.O. contacts
to close until the set time-delay value has elapsed. See
Figure 6. When the delay is activated, the LCD
alternately flashes the sensor temperature and ASd. The
delay may be set for 0 to 12 minutes in 1-minute
increments.

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