100/180 mm PAPERLESS GRAPHIC RECORDER: USER GUIDE
User Guide
Page 161
HA028910
Issue 13 Sep 16
4.3.16 MASTER COMMS (Cont.)
RECORDER/DAQ CONFIGURABLE PARAMETERS
TYPICAL RECORDER PARAMETERS
The following parameters may be accessible from a recorder or data acquisition unit, depending on
model number. Figure 4.3.16e, above, refers
Notes:
1. Items such as Scale, Zone and descriptor may be editable (white background) or not (grey back-
ground), depending on model.
2 This description includes only those items which are unique to input channels with Input Type =
Master Comms. For other items please see
section 4.3.3
.
Channel Number Allows the user to select the number of the channel to be confi gured. As soon as
Modbus master is selected as input type, the display changes from ‘Channel 1’ (for
example) to ‘Read 1’. This legend stays as ‘Read 1’ ‘until a descriptor is entered (be-
low), which immediately overwrites it.
Slave
Allows the user to select (from a picklist), the slave from which data is to be retrieved.
The picklist contains all the Remote Devices confi gured as slaves in the Master
Comms Confi guration described above.
Digital
Allows data to be read into a digital input.
Parameter
Allows the user to select Alarm setpoints, Process Value, Batch status (model de-
pendent) or ‘User defi ned’ to be selected. ‘User defi ned’ allows a (decimal) register
address to be entered
Scaling
For some slaves, scale zero (scale low) is returned as value 0 and full scale (scale high)
as value 65,535 (Hex FFFF) with intermediate values having proportionate values.
For example the value 15, would be represented as 32,767 (7FFF) for a channel scale
0 to 30, as would a value of 50 for a channel scaled 0 to 100, and a value of 45 for a
channel scaled 30 to 60. In order to convert this reading to an understandable value,
a scaling factor must be entered. If the low and high scale entries match the slave
channel’s scale, the master reading will be the same as the slave’s reading.
Selecting ‘High/Low’ allows Scale low and Scale high values to be entered for the
selected parameter. If ‘None’ is selected, the process value is displayed as a propor-
tion of 64k.
Point type
This item appears for Alarm setpoints and Process Value parameters only. Point type
allows the relevant point type (i.e. input channel, maths channel, totaliser etc.) in the
slave to be selected.
Point number
This item appears for Alarm setpoints and Process Value parameters only.
Point number allows the relevant point number in the slave to be selected. (If an
instrument is confi gured to use more than 100 math channels in the slave instrument
- see
section 4.3.22
).
Group Number
This item appears for Parameter = ‘Batch Status’ only. Group number allows that
group, the status of which is to be read, to be defi ned.
Process Value
Allows one of three rates to be set for reading the Process Value. The three rates
(Low, Medium and High) have the values set in the Master Comms confi guration.
Span
Where the input value is scaled (see above), this ‘Span’ setting sets the Zero and Full
Scale values for the channel. This is different from the situation obtaining in input
channels, where span and scale have different meanings.
Remaining items are as described in Channel Confi guration in
section 4.3.3
.
