A590-00-880 Issue D
3.14
Install additional safety equipment
If your Process Tool/control system needs to know the total flow rate of nitrogen to the system for
safety reasons, install suitable measurement equipment in the nitrogen supply pipeline.
If you use the nitrogen purges to dilute dangerous gases to a safe level, ensure that the system
shuts down if the nitrogen supply to the system fails.
If the sensors or microprocessors fail, the total flow rate of nitrogen displayed or output by the iH system may be
incorrect. If you need to know the total flow rate of nitrogen to the dry pump for safety reasons, you should therefore
fit suitable measurement equipment in the nitrogen supply pipeline. If you fit a rotameter, ensure that it is suitable
for use with nitrogen and that it is correctly calibrated.
If the nitrogen supply to the iH system fails, a warning message will be shown on the Pump Display Terminal (if fitted)
and will be sent to the Interface Module(s) connected to the iH system. Ensure that your installation is configured so
that it remains safe if there is a failure of the nitrogen supply to the iH system.
If an alarm condition is detected (and the iH system is not configured to 'run til crash' refer to
system will shutdown automatically. You must ensure that your installation remains safe if the iH system shuts down
automatically.
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WARNING
WARNING
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Section
4.4) the iH