THCD-401 Instruction Manual
Page 33 of 47
(e)
Setpoint source – ‘sps’
The setpoint source can be an internally set value (using, for example, the ‘spv’ command) or a percentage
(slave ratio) of one of the THCDs inputs. This source is set using this command and as with the other setpoint
commands, it takes two parameters. The first is the setpoint to set and the second is a number between 0 & 4,
identifying the source, as follows:
0 = Internal
1 = A percentage of input channel 1
2 = A percentage of input channel 2
3 = A percentage of input channel 3
4 = A percentage of input channel 4
Remember to use the ‘spv’ command or the front panel HMI to set the percentage value if the chosen source is
1-4.
(For more information on setpoint sources, see the Principles section – 7.4(b)).
The current sources of all setpoints can be retrieved by using the query ‘sps?’. The returned data is:
SP1 SOURCE: (<x>) <source identifier>
SP2 SOURCE: (<x>) <source identifier>
SP3 SOURCE: (<x>) <source identifier>
SP4 SOURCE: (<x>) <source identifier>
…where…
<x> = 0 to 4 (same as the second parameter above)
<source identifier> = string identifier for <x> : INT or SLVn where n is the input channel number. (You will see
these designations are used on the front panel HMI as well).
(f)
Setpoint initial value – ‘siv’
The setpoint value set with the ‘spv’ command (above) is not non-volatile. This command can be used to set an
initial setpoint value on system startup. It takes two parameters which are the setpoint to set and the initial
setpoint value.
The initial values of all setpoints can be retrieved using the query ‘siv?’. Returned data is:
SP1 INIT VAL: <initial setpoint 1 value>
SP2 INIT VAL: <initial setpoint 2value>
SP3 INIT VAL: <initial setpoint 3 value>
SP4 INIT VAL: <initial setpoint 4 value>
(g)
Setpoint initial mode – ‘sim’
As with the value, the setpoint mode set using the ‘spm’ command (above) is a volatile setting. Again this
command provides a way of setting an initial startup mode for any of the setpoints on power up of the THCD.
Again, it takes two parameters which are the setpoint to set and a number between 0 & 2, identifying the
initial mode, as follows:
0 = Auto mode
1 = Open mode
2 = Close mode
The initial modes of all setpoints can be retrieved using the query ‘sim?’. Returned data is: