Maintenance
Instruction manual 854 ATG Page 43
5.4.3 Replacing software
The actual software version can be withdrawn by requesting for item SV. Compare the combination of the
software versions of the XPU, SPU and optional board with the value of SV in the ‘set-up and maintenance
form, sent with every gauge.
Such a form, containing all the gauge and tank data, should always be available.
Else, do commissioning, and fill-out the form before changing any EPROM or NOVRAM.
Moreover, check before changing, if the combination of the software in EPROMs, located on the various
printed circuit boards, is compatible with your new software version.
Carefully read the instructions which are enclosed with the new EPROMs or NOVRAM.
Refer to section 5.4.2 for dismantling the electronic compartment and removing the boards.
Note:
A
fter installing an EPROM from a new software version the NOVRAM must be reformatted and the
parameters of the gauge has to be reprogrammed. If the set-up / maintenance data is lost,
go back to section 3.3.
Appendix E gives the layout of the different printed circuit boards with the position of the EPROMs and
NOVRAM.
5.4.4 Initializing NOVRAM
If a new software version is installed, or a feature has been added to the 854 level gauge, NOVRAM
initialization is required. With this procedure, all items are declared in the NOVRAM and filled with their
default value. After the initialization, reprogramming of all items is necessary.
When the 854 ATG is equipped with an XPU board, the NOVRAM is initialized as follows:
• Switch off mains supply.
• Open electronic compartment of the gauge.
• Switch over strap JA4 on the XPU board to position 0.
• Close electronic compartment.
• Apply mains supply to the gauge.
• A NOVRAM initializing message is shown on the display.
• Hold the test magnet in front of the display.
• When the message: “NOVRAM init completed” appears, switch off mains supply.
• Open electronic compartment of the gauge.
• Switch over strap JA4 on the XPU board to position 1.
• Close electronic compartment.
• Apply mains supply to the gauge.
Alternatively, and for the XPU-2 the only, the following procedure can be used:
When the gauge is powered, issue the IN command by the PET 3 times in sequence. After the first
command, use the “↑” key and “enter” key. No other command may interfere
in this sequence.
Note:
To prevent other commands in the initialization sequence, the Honeywell Enraf field bus lines may,
temporary, be disconnected.