07Operation and shutdown

Front-panel LED#

A single LED on the front panel shows the unit's state by colour. The colours mean the same as on the HXB-V1. For the detailed state, check the Status field at the top of the control app.

Daily start-up#

Switch the dryer on first and start the HXB-V1 units after it. The first start is done with us, as in the First start chapter.

Before you start#

• There is no active emergency stop (ES) or fault stop (FS) alarm in Alarms & Events.
• The PURGE, DEPR. and DRAIN vents run to safe discharge points and are unobstructed. There are no valves in the vent lines.
• The line after H2 OUT is open, so the product hydrogen has somewhere to go.
• The air openings at the rear of the unit are clear.

Sequence#

1. Switch the HXD-V1 on at ON/OFF.
2. Start the dryer project in the app and check MQTT ONLINE.
3. On the P&ID screen, turn Temperature Control ON. Check the regeneration temperature.
4. Turn Cycle time control ON.
   • The cycle cannot start while Temperature Control is off.
5. Start the HXB-V1 units. Once inlet pressure rises, the dryer moves from STANDBY into operation.

Regeneration settings#

The three settings below are the ones you can change on the dryer. Change them under Temperature Control and Cycle time control on the control app's P&ID screen.

• Keep the defaults unless HydroXpand advises otherwise.
• A longer cycle leaves the online tower taking up water for longer. If the outlet dew point rises, first check that this setting has not been changed.
• If a tower runs 30 °C or more above the regeneration temperature, the unit makes an emergency stop (ES_03).

Monitoring during operation#

During operation, watch the values below on the P&ID and Dashboard screens. Outside the normal range the unit warns or stops, with the alarm code shown in the right-hand column.

Trends matter more than a single reading. Follow them with the temperature and pressure charts on the Dashboard and the daily and monthly items in the check lists.

Normal shutdown#

To stop, reverse the start order and stop the HXB-V1 units first. To take the unit out of service for storage or return, follow the shutdown steps in the Decommissioning chapter.

1. Stop hydrogen production at the HXB-V1 units.
2. Turn Cycle time control OFF, then Temperature Control OFF.
   • Temperature Control cannot be turned off while the cycle is running.
3. For a long stop, switch off at ON/OFF. Do not open a tower that was heating until it has cooled.

PLC and SCADA integration (Modbus TCP)#

The dryer supports Modbus TCP over Ethernet. Instead of the control app, your site PLC or SCADA system can take the operating state and readings and integrate the unit into your plant.

Ask us through a technical enquiry and we will send the latest register map. Agree the scope of integration with us when you order.