VEGA Bitumen Overfill Protection Systems and Panels Part 3

Tank Monitoring Panel

Each Tank Monitoring Panel shares the same functionality, taking inputs either from an existing tank level control panel or direct from an independent high-high level switch and continuous level measurement transmitter, to provide alarms in accordance with RBA guidelines. They are designed to be mounted near the tanker loading point for driver/loading information and alarms. 

 

High Level Alarms

Signals for high-high and high levels are taken into the monitoring panel from the high level switch and level transmitter  or  an existing associated tank level control panel. Volt-free contact inputs are in the bitumen tank panel – 1 x N/C for the high-high level switch input, 1 x N/O for the high level (taken from the continuous level measurement system) these alarm outputs control the ‘traffic light system’ (left) and provide outputs to the main alarm panel.

 

 

 

Continuous Level Measurement System

To enable the tank contents and ullage to be displayed (i.e. if the tank has the capacity to accept 28 tonnes of bitumen – a standard lorry tanker capacity) a 4-20mA analogue signal is taken from the continuous level transmitter on the tank. The signal is used to display both the tank contents, ullage and derive any level alarms (except for the high – high). The mathematical functions to enable this are preformed within a programmable controller (smart relay), which will operate the traffic light system as recommended by the RBA.

 

Panel alarm controls

Each monitoring panel has two spring-return key switches for silencing the high or high-high alarm. The logic behind this is that the tanker driver will be formally issued with a key at the weigh-bridge and with the panel adjacent to the fill point, has the ability to silence the alarm if needed.

 

If the alarm is not silenced with the key switch, it will sound for 3 minutes (current setting) then automatically turn off. The alarm will also automatically reset once the level has been returned within safe working limits.

 

Panel Self diagnostics

VEGA level switches and transmitters are designed to warn of failure. For example, if the 4-20mA signal is lost or the device goes into fault (output <22mA), all lights on both the monitoring panel and alarm panel will flash, currently this is set to 500ms on, 500ms off. Additionally, any fault or signal detected is displayed on a screen built into the controller for both commissioning and fault finding purposes.

 

Testing and Service indicator

All the lights are based on super bright LED technology, which will outlive a bulb many times. But there is always the possibility the light could have been damaged another way, so a lamp test function is provided to make sure all the lights are functioning correctly.

 

Overfill Alarm System Test switch is supplied on the panel to ensure all level alarms and alarm annunciators are functioning correctly.

 

A Service Indication Light (S.I.L.) is incorporated into the main alarm panel to indicate a reminder when a scheduled service (normally set to 12 months) is required. It also has a service contact number and panel ID printed below it to make it quick and easy to identify your panel and the instruments you have connected on our database.

 

 

All panels are supplied with wiring drawings/diagrams. We are happy to assist with site surveys and advice for on-site electrical contractors on their installation. Full commissioning and ongoing fixed price service contracts for annual inspection and testing are available.

 

If you missed parts 1 & 2, you can find links to them below:

 

VEGA Bitumen Tank Level Monitoring Panels Part 1

 

VEGA Bitumen Tank Level Monitoring Panels Part 2

 

In the final part of this series , we look at additional options for the bitumen tank application. 

VEGA Bitumen Safety System Monitoring Panels Part 4

 

Please do not hesitate to contact us if there is anything we can do for you.

Related posts:

1. VEGA Bitumen Overfill Safety System Monitoring Panels Part 2
2. VEGA Bitumen Safety System Monitoring Panels Part 4
3. VEGA Bitumen Tank Level Monitoring Panels Part 1
4. Silo level monitoring Part 3: Recommended Overfill Prevention Devices for Bulk Solids
5. Silo level monitoring Part 2: When a Silo High Level Alarm is not enough…