ABACUS MPA2A User manual

Parameter Setting Example via Menu
To Adjust Hi alarm value
Press mute & adj together and hold
Press res (once)
Release mute & adj
Press hi 7 times
(display will read HI ALM = (Value))
Press adj
Press adj
(display will read ADJUST THE VALUE)
Press hi to increase value or lo to decrease value
Press set
(within30 seconds or display will go back to normal & changes will be ignored)
For Quick Set of hi and lo Alarm Setpoint
Press hi or lo
Press adj
Use hi or lo to adjust value
Press adj to select ‘ENABLED’
Press set
(within 30 seconds or display will go back to normal & changes will be ignored)
Abacus Instruments; 13C Old Bridge Way, Shefford, Beds., England ,SG17 5HQ
Phone; [phone] Fax; [phone] www.abacusinstruments.com
MPA2A Alarm
Instructions for use
Note: The internal battery link between terminals 6 & 7 has been removed for shipping.
This link must be remade for the unit to operate.
Connections:-
240V ac Supply Terminal 1 (Live)
Terminal 2 (Neutral)
Terminal 3 (Earth)
Battery Link Terminal 6 & 7
Alarm Relay Terminal 8 (Common)
Terminal 9 (N/C)
Terminal 10 (N/O)
Note: The relay is fail safe hence N/C contacts
are closed when unit is in alarm condition
Buzzer Terminal 11 +
Terminal 12 –
Defrost Switch Terminal 13 & 14 (Note Closed cct = Defrost)
Door Switch Terminal 15 & 14 (Note Closed cct = Alarm) (Factory selectable)
PT1000 sensor Terminal 23 Red (GND)
Terminal 24 White

Alarm Parameters
Mute Delay
Set in minutes 0 – 99, this is the period that the buzzer will be muted for if the ‘‘mute’’ button is
pressed following an alarm. If the alarm is still present on time out of the mute period then the
buzzer will re-sound.
If an additional alarm occures during the mute period then the buzzer will also sound.
Door Alarm Delay
Set in minutes 0 – 99, during this period the LED indicator will flash. On time out of the door delay
period the LED will light solid, the buzzer will sound and the alarm relay contacts N/C will close.
Power Delay
Factory set to 0. This parameter is for special options and should not be altered without reference to
the manufacturers.
Defrost Delay
Set in minutes 0 – 99, whenever the defrost contacts are closed all temperature alarms are ignored.
The door and power fail alarms are stil active. When the defrost is complete and the contact opens
the defrost delay period starts. Again during this period all temperature alarms are ignored.
Offset
Factory set to 0. This parameter is for special options and should not be altered without reference to
the manufacturers.
Scale
Factory set to 0. This parameter is for special options and should not be altered without reference to
the manufacturers.
Length
Factory set to 0. This parameter is for special options and should not be altered without reference to
the manufacturers.
Hi Temp Alarm
Set in degrees C –99/+99
Lo Temp Alarm
Set in degrees C –99/+99
Hi Temp Alarm Delay
Set in minutes 0 – 99, during this period the LED indicator will flash. On time out of the Hi Temp
Alarm Delay the LED will light solid, the buzzer will sound and the alarm relay contacts N/C will
close.
Lo Temp Alarm Delay
Set in minutes 0 – 99, during this period the LED indicator will flash. On time out of the Lo Temp
Alarm Delay the LED will light solid, the buzzer will sound and the alarm relay contacts N/C will
close.
NOTE. Where used the alarm delay function should not be set to less than 5
minuites.
i.e set to 0 (default) or >5 mins
Operator Settings
The alarm parameters are found in the settings menu.
This is accessed by pressing and holding the adj & ‘mute’ buttons together and then
pressing the ‘res’ button. The alarm parameters can be scrolled through using the hi and
lo buttons. When the desired parameter is displayed the adj button can be pressed to
input a new value. This is done using the hi and lo buttons.
On completion the ‘set’ button must be pressed to store the set values.
Note: The display will revert to normal after 30 seconds. If a change has been made but
the ‘set’ button has not been pressed then the new value will not be stored.
Alarm Test
During normal operation pressing the ‘res’ button will provide a 3 second display, buzzer
and LED test. This does not alter the alarm relay contacts.
Battery Back-up
The internal battery will provide a minimum of 2 hours battery backup following a power
failure. This can be extended by connecting external batteries.
Please contact the manufacturer for details.
Instrument Mounting
The MPA-2a is a panel mounted unit and can be secured with the two panel clips located
at the top and bottom of the unit. Turning them clockwise will tighten them and anti-
clockwise will release them.(See below)