Sampling

Acquire can automatically send out signals to the sampler while a batch is being transferred.

Given a can size of 10 litres and a grab size of 1cc means that 10,000 individual grabs can be made. Of course, the greater the number of samples taken in a batch the more representative the sample. These grabs should be made over the entire course of a batch. If a ship is being loaded with 850,000 barrels, a grab will be made for every 85 barrels.

Acquire will automatically calculate when to send out grab requests to the sampler. At the moment these sampler requests are made directly with the flow computer or PLC.

Configuring the Sampler

Select 'Batching…' from the 'Config' menu.
Double click on the station to edit it.

Configuring the Sampler

Specify the fields as follows:

Field	Description
Sample Can Size	This is the size of the sampler can. The units do not matter as long as they are the same as the grab size units.
Grab Size	This is the size of an individual grab. The units do not matter as long as they are the same as the sample can size units. Number of Grabs = Sample Can Size / Grab Size
Grab Command Field	This is the field that Acquire will write to when issuing a grab command. It can be any field in the Modbus map from a flowcomputer, PLC or sampler.
Grab Command Write Value	This is the value that should be written to the Grab Command Field when to initiate a grab.

Once these fields have been specified, the sample will automatically be taken at the correct interval based on the combined station flow rate.

Note: Acquire assumes an empty sample can when deciding how many grabs to make.

If stream batching has been enabled, then each stream can have its own sampler assigned to it.