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THREE BUTTON RULES

• Always start by pushing the 

SELECT

button, watch what is 

displayed. Which menu are you in?

—  StUP  —  CLOC  —  DEFr  —  tEM  —  VALv  —  DiSP  —

and cycles back to StUP

• Press the 

SELECT

button until you are in the proper menu. Once in

the proper menu press the 

UP

or 

DOWN

button to enter the menu and

to scroll through the menu.

• Once at the menu item that you want, press the 

SELECT

button until

the item flashes between the value and the title. You may have to press

the

SELECT

button more than once to get the item to flash. 

• Then press the

UP

or 

DOWN

button to change the item.

• Remember to push the 

SELECT

button to save the item. 

Also remember to set the passcode before any items can be changed.

• Pressing the 

UP

or 

DOWN

buttons at the same time acts as an escape

to go back out of the menus.

Safe-NET

DISPLAY & ALARM MODULES

DESCRIPTION

Safe-NET Display Module

The Safe-NET Display Module, shown below, is a temperature-

monitoring device. The display module reads and displays temperature

sensed by the product simulator temperature sensor mounted in the

refrigerated space. The display module notifies the user of alarms based

on preset alarm conditions.

OPERATION

Normal

During normal operating conditions, the product simulator tempera-

ture is displayed. The GREEN LED on the alarm module is lighted .

Product Temperature Alarms

The display module generates an alarm if the product simulator 

temperature rises above the high alarm set point or drops below the

low alarm set point for the preset time duration.

When the display module generates a high temperature alarm, the

RED LED on the display module is lighted. Every 12 seconds, 

PrHi

is

displayed for 3 seconds; for the remaining time, the product simulator

temperature is displayed.

When the display module generates a low temperature alarm, the 

RED LED on the display module is lighted. Every 12 seconds, 

PrLo

is

displayed for 3 seconds; for the remaining time, the product simulator

temperature is displayed.

For either alarm, the beeper on the alarm board beeps every 6 seconds.

Power Failure

If external power to the unit is interrupted, the backup battery on the

alarm board supplies power to maintain the non-volatile memory in

the display module.

To conserve power, the display LEDs are blanked except for a period of

6 seconds every 3 minutes when product temperature is displayed.

Product temperature alarms can be generated during external power

loss. The audible alarm is active only for product temperature alarms.

Low Battery

During normal operating conditions, the alarm module monitors 

battery condition. The display shows 

bAtt

when the battery becomes

low on power and the beeper on the alarm board beeps every 2 minutes

to indicate a low battery condition. 

The low battery audible alarm is

active only when external power is applied.

Connection Failure

Loss of communication between the display module and the alarm

module activates an alarm. When the display module generates a loss of

communication alarm, the RED LED on the display module is lighted.

Every 12 seconds, 

A-Er

is displayed for 3 seconds; for the remaining

time, the product simulator temperature is displayed. The beeper on

alarm board beeps every 30 seconds. The 

A-Er

audible alarm is active

only when external power is applied.

Precedence of Alarms

Severity of the alarm determines the beeper action. The following table

shows the priority of the alarms.

An alarm with higher severity takes precedence over a low severity

alarm. For example, if there is a product alarm and low battery alarm:

The alarm board beeper beeps every 6 seconds to indicate the 

product temperature alarm.

Indication of the low battery alarm is ignored by the beeper, but 

is active in the display.

Every 12 seconds, the display shows 

PrHi

for 3 seconds followed 

by 

bAtt

for 3 seconds. For the remaining time, product simulator

temperature is displayed.

Alarm Set Points

Refer to the manual that came with the specific case or model.

Notes:

A high temperature alarm typically activates during case startup.

This is normal since the refrigerated space requires an extended period

to reach operating temperature. Product must not be loaded until

operating temperature is reached. Premature stocking may result in

product loss.

Battery backup operation is possible for up to 6 hours. The initial

condition of the battery determines the length of time. Operation of

Safe-NET is compromised once the battery runs low. Product integrity

cannot be ensured until power is restored and the battery is replaced.

MODIFYING SETTINGS 

The Safe-NET display module stores alarm set points and alarm delay

times for monitoring cases. The suggested default set points may be

modified.

Use a flat, narrow tool such as a small screwdriver to remove the cover

of the display module.

IMPORTANT!

Hussmann recommends against changing

any parameter

value other than those described herein. Modification of

any other parameter may result in unpredictable Safe-NET

operation.

• The user must monitor each case after altering product

alarm set points and/or product alarm time delays to verify

proper operation.

There are three visible buttons on the left hand side of the display

board

,

as indicated in Figure 2 on Page 1. Although labels are not

clear, buttons can be determined by their location.

The SELECT button is located near the top edge of the display board.

It is used to select the menus and to edit the menus.

The UP button is the left button of the two buttons located on the

bottom lineup of the display board. The DOWN is the right button of

the two buttons located on the bottom lineup of the display board.

The UP and DOWN buttons are used to move within and between

menus, and to increment or decrement values.

Safe-NET™ Self-contained Operating Instruction

Page 

2 of 8 — P/N 0485005_B

© 2007 Hussmann Corporation • Bridgeton, Missouri  63044-2483 U.S.A.

www.hussmann.com/cstore/c_techinfo.htm

20 June 2007

Safe-NET Display Module with Top Cover

LED Indicators

Safe-NET Display Module with Cover Removed

Safe-NET Alarm Module

Green LED

SELECT Button

UP Button

DOWN Button

Alarm

Display 

Action

Beeper 

OFF Time
(seconds)

Severity

Product

HIGH/LOW

Alarm

PrHi/PrLo

6

1

Connection

Failure

A-Er

30

2

Low Battery

bAtt

120

3

Summary of Contents for Safe-NET

Page 1: ... need for separate wiring Sensors in each case are harnessed together to a single wire leading to the display module Sensors are designed for rugged durability Should a sensor fail it can be replaced Optional Wireless Hand held Controller and or PC Control The wireless controller communicates with the display unit through an infrared sensor This allows setups and queries which can also be performe...

Page 2: ...ay module is lighted Every 12 seconds A Er is displayed for 3 seconds for the remaining time the product simulator temperature is displayed The beeper on alarm board beeps every 30 seconds The A Er audible alarm is active only when external power is applied Precedence of Alarms Severity of the alarm determines the beeper action The following table shows the priority of the alarms An alarm with hig...

Page 3: ...read the sensors DischargeAir HighAlarm dSHi This alarm is generated when the average discharge air temperature in the case over the programmed alarm delay time is higher than the HighAlarm value stored in the control This alarm will clear if the average discharge air temperature goes below the High alarm value THIS ALARM IS AVAILABLE ONLY IF DISCHARGE SENSORS ARE INSTALLED DischargeAir LowAlarm d...

Page 4: ...rdingly in the detailed parameter descriptions PASSWORD PROTECTION Parameters that are critical to proper equipment performance cannot be modified until a numeric password is entered into the Safe NET display module This prevents accidental or malicious changes in the Safe NET system from occurring Entering the password is done in the SETUP menu At the top of the SETUP menu press the UP button on ...

Page 5: ...g F the ON OFF control method will attempt to maintain the 10º by cycling the control device ON at temperatures above 10º and OFF at 0º This temperature control is superceded by a fixed minimum ON time of 3 minutes Hence lower DIFF settings will result in tighter temperature control but more frequent control device compressor valve cycling Conversely higher DIFF settings will reduce control device...

Page 6: ...at a valid PASSWORD be entered first DTYP The Safe NET system is capable of controlling defrost activity and scheduling The Safe NET system is capable of controlling six types of defrost OffC DET Mod ELE2 GAS and ELE1 1 OffC Off Cycle During off cycle defrost refrigeration to the fixture is stopped by either cycling off the compressor if so equipped shutting off the liquid line solenoid valve shut...

Page 7: ...ed as represented to the right Missing or non connected sensors will not appear in the designated sequence Average temperatures are available to view so long as the associated sensing devices are attached DSAV DischargeAirAverage RTAV ReturnAirAverage PDAV ProductAverage T LO LowestTermination Sensor Reading ILET Evaporator Inlet OLET Evaporator Outlet TSNL LeftTermination Sensor TSNC CenterTermin...

Page 8: ...e desired setting is displayed press the SELECT button on the Safe NET display module to store the new value to NV memory The display will revert to cycling between DISP and the new value Note One or more sensors of the type selected must be installed to support the selection Alarm Module OPTIONAL The alarm module is an additional feature to Safe NET The alarm module supplies power to the display ...

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