Remote Digital Display Alarm Indicator

Product Overview

The PureAire Remote Digital Display Alarm Indicator provides continuous information on the status of PureAire's oxygen deficiency, carbon dioxide monitors, O2 analyzers, and gas detectors. All PureAire safety monitors feature a built-in mA output. The Remote Display Alarm connects to the monitor's input power and mA output connection.

A recommended connection uses an 18 AWG, three-conductor, shielded control and instrumentation cable, such as Belden 8770 or equivalent. The maximum permissible cable length is 250 feet.

The Remote Display can also be connected to a programmable logic controller (PLC) to provide simultaneous alarm and status indications in multiple locations throughout a facility.

Visual Description: A white and blue device with a digital display showing "20.8". Below the display are three indicator lights labeled "AL2", "AL1", and "FAULT". The device is labeled "Remote Display" and "% O2".

How to Mount the Remote Display Alarm Indicator

Follow these steps to mount the Remote Display Alarm Indicator:

1. Open the two side doors to expose the front panel screws.
2. Loosen the four screws to separate the front panel from the case.

Mount the case to a wall or other flat surface using the four provided through-holes for fastening. The case is designed for flush mounting.

Note: The front cover can be removed by gently pulling on the plastic hinges, which remain attached to the front cover. To reattach the front cover, push the plastic hinges back into the case.

Visual Description: Images show the front panel of the device, the device with the front panel removed, and the back of the case with mounting holes.

How to Wire the Remote Display Alarm Indicator

An 18 AWG, three-conductor, shielded control and instrumentation cable, such as Belden 8770 or equivalent, is recommended for the connection.

Wiring Diagrams:

Single Display Wiring

Connects an O2 MONITOR to a REMOTE DISPLAY. Connections include +V, MA, and GND. The REMOTE DISPLAY has terminals for SHLD, +24, MA, GND, MA OUT, and MA IN.

Two Displays Wiring

Connects an O2 MONITOR to two REMOTE DISPLAYS. The first REMOTE DISPLAY is wired directly, and the second REMOTE DISPLAY has a jumper that needs to be removed ("REMOVE JUMPER!").

Display & PLC Wiring

Connects an O2 MONITOR to a REMOTE DISPLAY and a PLC. The REMOTE DISPLAY is wired as before. The PLC is connected via "ANALOG (CURRENT)" and "GND" terminals, or "ANALOG (VOLTAGE, 0-5VDC)" and "GND" terminals, with a 250Ω, 0.25W resistor shown in the voltage path.

Identification of Switches and Controls

The Remote Display Alarm Indicator features several switches and buttons for configuration:

1. Alarm Adjusting Switches

Used to select the alarm level to be adjusted. Factory settings are 19.5% for Alarm 1 and 18% for Alarm 2.

2. Alarm Polarity Switches

Select when alarms activate. For oxygen, set to "Below" (alarms activate if readings drop below a set ambient level, e.g., 19.5%). For toxic gas monitors, set to "Above". Factory default is typically "Below" for oxygen.

3. Range Auto Adjustment Switches

Used to adjust the zero and full scale readings. When a 4mA and 20mA signal is sent from the monitor, pushing these switches automatically adjusts the zero and full scale readings on the Remote Digital Display.

4. Alarm Adjusting Buttons

Buttons used to increase (UP) or decrease (DOWN) the alarm settings.

5. Horn On/Off Switch

Turns the internal audio horn on or off. When ON, any alarm activates the audible horn. Turn to OFF to disable the internal horn.

Visual Description: A close-up of the circuit board showing labeled switches and buttons: "Alarm adjusting switches", "Alarm Polarity switches", "Range auto adjustment switches", "Alarm adjusting buttons", and "Horn On Off Switch". A note indicates: "Do not remove jumper unless connecting to a second remote display or a PLC."

How to Setup and Operate the Remote Display

Caution: Entering setup menus will disable real-time oxygen readings.

After wiring the remote display to your monitor, turn on the monitor's power. During the warm-up period (approximately 4 minutes), the remote display will show a yellow fault LED and the display will read "FLt", indicating the monitor is in fault. This indication will clear once the warm-up is complete.

Visual Description: Two images show the display during warm-up ("FLt") and after warm-up ("20.9").

How to Set the Zero and Full Scale Range

This procedure is performed in the field to calibrate the display based on cable length and monitor output.

Setting Zero (4mA):

1. On your monitor, enter the password and select the "Set 4-20mA loop" menu.
2. Push the joystick right to select "Set 4mA Zero", then push the joystick right again to activate. This sends a 4mA signal.
3. On the back of the remote display, push the ZERO button for 3 seconds. The display will reset and adjust to the new zero.
4. (Optional) Push the joystick up or down to fine-tune the zero reading. Both AL1 and AL2 LEDs will illuminate during this process.
5. To exit the Zero menu, push the joystick left once.

Setting Span (20mA):

1. Push the joystick down to select "Set 20mA Span", then push the joystick right to activate. This sends a 20mA signal.
2. On the back of the remote display, push the SPAN button for 3 seconds. The display will reset and adjust to the new span (e.g., 25%).
3. (Optional) Push the joystick up or down to fine-tune the full scale reading.

To return to the main menu, push the Joystick left until the monitor displays "Oxygen 0-25%" on the top line.

Note: To fine-tune the reading to match the monitor, use the "Set 20mA Span" menu and adjust with the joystick.

Caution: NEVER push the SPAN button while in the measuring mode, as it will automatically adjust the display to 25.0% and require recalibration.

Visual Description: Images show the display reading "0.0" during zero adjustment and "25.0" during span adjustment.

How to Set the Internal Alarms

The Remote Display has two user-selectable alarms, each with a distinct horn tone.

Factory Presets (unless specified otherwise):

• Oxygen Monitors (0-25%, 0-30%, 0-95%): AL1 = 19.5%, AL2 = 18%
• Oxygen Monitors 1000 ppm: AL1 = 20 ppm, AL2 = 40 ppm
• Carbon Dioxide Monitors: AL1 = 50 ppm, AL2 = 100 ppm x 10
• LEL 0-100%: AL1 = 20%, AL2 = 40%
• Gas Detectors 0-30 ppm: AL1 = 5 ppm, AL2 = 10 ppm

Note: Alarm levels can be changed in the field.

To Set Alarm 1:

1. Press and hold the Alarm 1 button for two seconds to enter alarm change mode. The current alarm setting will display, and the rightmost decimal point will be lit.
2. Use the UP or DOWN buttons to increase or decrease the alarm value.
3. When finished, press and hold the Alarm 1 button for two seconds to return to monitoring mode.

To Set Alarm 2:

1. Press and hold the Alarm 2 button for two seconds to enter alarm change mode. The current alarm setting will display, and the leftmost decimal point will be lit.
2. Use the UP or DOWN buttons to increase or decrease the alarm value.
3. When finished, press and hold the Alarm 2 button for two seconds to return to monitoring mode.