Solartron Mobrey 3595 4C, User Manual

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3595 4C User Manual Part Two IMP Commands
35952350 (CH01/AA)
1-49
CH LL
(CHannel Low Limit)
CH n LL limit i
Where: n is an integer that defines the channel number, in the range 1
≤
n
≤
18
< limit > is an IEEE 754 floating-point number that defines the limit (in channel units)
< i > is an IEEE 754 floating-point number that defines the limits for hysteresis (in units)
Function: Defines the low limit for alarm checking on a channel. This is used only in conjunction with
the
CH GO command.
The effect of hysteresis is described in the following example:
1.
The limit for a thermocouple is set to 10
°
C.
2.
Hysteresis is set to 3.
3.
With a falling temperature, an alarm is signalled at 7
°
C. The signal remains until the
temperature rises above 13
°
C.
See also: CH HL and CH GO
CH GO
(CHannel Group alarm Output)
CH n GO string
Where: n is an integer that defines the digital output channel number, 19 or 20
< string > is a string defining on which the analogue channels an alarm check is required.
The format for < string > is:
pA
1
A
2
A
3
…A
36
p defines the output state of channel n for alarm detected:
•
p = 2, disable alarm checking on channel n
•
p = 1, FET on: switch closed, i.e. as MODE 801
•
p = 0, FET off: switch closed, i.e. as MODE 800
A
n
is the identity of an alarm check and consists of an analogue channel number, in the
range 1 through 18, and the character H or L. The ‘H’ specifies a high limit alarm check
(See
CH HL ); ‘L’ specifies the low limit alarm check (See CH LL ).
Function: Defines the group of alarms to be associated with a digital output. If any of the alarms are
active (OR logic), the digital output will be active. Only the channels specified in the last
CH GO command are checked.
The CH GO command provides for alarm checking on all 18 analogue channels. Checking is
against the high and low limits defined by the CH HL and CH LL commands. On all analogue
channels, it is possible to specify a high limit alarm check, or a low limit alarm check, or both.
Specifying both alarm limit checks is equivalent to specifying an ‘out-of-window’ check. (Note
that it is not possible to specify an ‘in-window’ check by specifying a high limit that is less than
the low limit.)
See also: CH HL and CH LL.