
Lake Shore Model 340 Temperature Controller User’s Manual
9-28
Remote Operation
CLIMIT
Configure Control Loop Limit Parameters
Input:
CLIMIT <loop>, [<SP limit value>], [<positive slope value>], [<negative slope value>],
[<max current>], [<max range>]
Returned:
Nothing
Remarks:
Configure control loop limits.
<loop>
Specifies which loop to configure.
<SP limit value>
Specifies loop setpoint limit and at what reading the loop turns off
output.
<positive slope value>
Specifies maximum positive change in output.
<negative slope value>
Specifies maximum negative change in output.
<max current>
Specifies maximum current for loop 1 heater output (Paragraph
6.12.1). Valid entries:
1
= 0.25 A,
2
= 0.5 A,
3
= 1.0 A,
4
= 2.0 A.
<max range>
Specifies maximum loop 1 heater range (Paragraph 6.13.3). Valid
entries:
0
-
5
.
Example: CLIMIT 1, 325.0, 10, 0[term] -
Control Loop 1 limits the setpoint to 325, turns off output when
the reading (based on the setpoint units) reaches 325, limits the change in the output to
+10% with no limit on the output going down.
CLIMIT?
Query Control Loop Limit Parameters
Input: CLIMIT?
<loop>
Returned: <SP limit value>, <positive slope value>, <negative slope value>, <max current>, <max
range>
. Format:
±
nnn.nnnE
±
n,nnn.n,nnn.n,n,n[term]
Remarks:
Returns parameters for control loop limits. See the
CLIMIT
command for parameter
descriptions.
<loop>
specifies which loop to query.
CMODE
Configure Control Loop Mode
Input:
CMODE <loop>, <mode>
Returned:
Nothing
Remarks:
Configures the control mode for a control loop.
<loop>
Specifies which loop to configure.
<mode>
Specifies the control mode. Valid entries:
1
= Manual PID,
2
= Zone,
3
= Open Loop,
4
= AutoTune PID,
5
= AutoTune PI,
6
= AutoTune P.
Example: CMODE 1, 4[term] -
Control Loop 1 uses PID AutoTuning.
CMODE?
Query Control Loop Mode
Input: CMODE?
<loop>
Returned: <mode>
.
Format:
n[term]
Remarks:
Returns the control mode for a control loop. See the
CMODE
command for parameter
descriptions.
<loop>
specifies which loop to query.
COMM
Configure Serial Interface Parameters
Input:
COMM [<terminator>], [<bps>], [<parity>]
Returned:
Nothing
Remarks:
Configures the serial interface parameters.
<terminator>
Specifies the terminator:
1
= <CR><LF>,
2
= <LF><CR>,
3
= <CR>,
4
= <LF>.
<bps>
Specifies the bits per second (bps) rate. Valid entries:
1
= 300,
2
= 1200,
3
= 2400,
4
= 4800,
5
= 9600,
6
= 19200
<parity>
Specifies communication parity. Valid entries:
1
= 7 data bits, 1 stop bit, odd parity;
2
= 7 data bits, 1 stop bit, even parity;
3
= 8 data bits, 1 stop bit, no parity.
Example: COMM 1, 6, 3[term] -
After receiving the current terminator, the instrument responds at
19,200 bps using 8 data bits, 1 stop bit, no parity, and <CR><LF> as a terminator.