The space on the backup SRAM required for saving the Alarm History data depends on the type of display unit and the number of [Records] of all blocks, the number of registered messages (addresses) and the [Alarm Type] settings.
When no message is registered, the data size is 0 bytes, regardless of the [Backup History] setting.
When the [Alarm Type] is [Extended], the accumulated time and number of occurrences are not saved in backup SRAM.
When using GP-4100 series (excluding GP-411*T3), the frequency at which alarm history data is saved to virtual backup memory is defined in the [Common Settings] menu's [Alarm] editor, [Storage Frequency] field.
The capacity of the backup memory (SRAM) or virtual backup memory that can be used for Alarm History data depends on the type of display unit and the space used by other data. For details about backup memory (SRAM), please see the following.
2.3 About the Display Unit's Internal Data
To check the backup memory (SRAM) usage, from the [Project (F)] menu, point to [Information (I)], select [Project Information (I)], and then select [SRAM Information].
When [Read Data From Each Alarm] is not selected (i.e., when [Number of Address] is zero), the underlined portions in the following calculations become 0 byte.
Calculation 1
If you are using the SP5000 series, GP4000 series (excluding GP-410*), LT4000 series, or IPC series, use the following calculations.
When the [Alarm Type] is [Basic] (in bytes)
1104 + Block 1 Records x {44 + 4 + (Number of Addresses+ 15) / 16 x 4 +Number of Addressesx 4} + (Apply the same calculation as Block 1 for Blocks 2 to 8) + (4 x Number of registered messages) + (16 x Number of registered messages) + (4 x Number of registered messages)] |
When the [Alarm Type] is [Extended] (in bytes)
1104 + Block 1 Records x {44 + 4 + (Number of Addresses + 15) / 16 x 4 + Number of Addresses x 4} + (Apply the same calculation as Block 1 for Blocks 2 to 8) +(Block 1 registered message number) + 31)/32 x 4 + (Apply the same calculation as Block 1 for Blocks 2 to 8) |
Calculation 2
If you are using the GP3000 series, GP-4100 series (Monochrome Model), LT3000 series, or ST3000, use the following calculation.
When the [Alarm Type] is [Basic] (in bytes)
576 + Block 1 Records x {28 + 4 + (Number of Addresses + 15) / 16 x 4 + Number of Addresses x 4} + (Apply the same calculation as Block 1 for Blocks 2 to 8) + (4 x Number of registered messages) + (16 x Number of registered messages) + (4 x Number of registered messages)] |
When the [Alarm Type] is [Extended] (in bytes)
576 + Block 1 Records x {28 + 4 + (Number of Addresses + 15) / 16 x 4 + Number of Addresses x 4} + (Apply the same calculation as Block 1 for Blocks 2 to 8) +(Block 1 registered message number) + 31)/32 x 4 + (Apply the same calculation as Block 1 for Blocks 2 to 8) |
Calculation Examples
Setting |
Description |
Backup Alarm History |
Set |
Setting for Block 1 |
- |
Number of Records for Block 1 |
768 |
Number of Addresses for Block 1 |
3 |
Number of Registered Messages for Block 1 |
2048 |
Settings for Blocks 2 - 8 |
None |
For IPC Series with the [Alarm Type] set to [Basic]
1104 + [768 x {44 + 4 + (3 + 15) / 16 x 4 + 3 x 4}] + (4 x 2048) + (16 x 2048) + (4 x 2048)
= 1104 + {768 x (44 + 4 + 4 + 12)} + (4 x 2048) + (16 x 2048) + (4 x 2048)
= 99408 bytes (approximately 97 KB)
For IPC Series with the [Alarm Type] set to [Extended]
1104 + [768 x {44 + 4 + (3 + 15) / 16 x 4 + 3 x 4}] + {(2048 + 31) / 32 } x 4
= 1104 + {768 x (44 + 4 + 4 + 12)} + 64 x 4
= 50512 bytes (approximately 49 KB)
For GP3000 Series with the [Alarm Type] set to [Basic]
576 + [768 x {28 + 4 + (3 + 15) / 16 x 4 + 3 x 4}] + (4 x 2048) + (16 x 2048) + (4 x 2048)
= 576 + {768 x (28 + 4 + 4 + 12)} + (4 x 2048) + (16 x 2048) + (4 x 2048)
= 98880 bytes (approximately 96 KB)
For GP3000 Series with the [Alarm Type] set to [Extended]
576 + [768 x {28 + 4 + (3 + 15) / 16 x 4 + 3 x 4}] + {(2048 + 31) / 32 } x 4
= 576 + {768 x (28 + 4 + 4 + 12)} + 64 x 4
= 49984 bytes (approximately 48 KB)