Output Related Commands

Heater Outputs 1, 2, 3, and 4 are traditional control loop heater outputs for a cryogenic temperature controller. The 4 outputs are identical current sources, with a maximum current output of 2 A and a compliance voltage limit of 50 VDC. For a maximum power output of 100 W, the heaters are optimally designed to drive 25 Ω loads. However, the heaters can drive loads ranging from 10 Ω to 100 Ω.

When setting up the heaters using the HTRSET command, they can be configured in terms of output power, or output current. The heater resistance and max output parameters work together to limit the maximum available power into the resistive heater. This is useful for preventing heater damage or limiting the maximum heater power into the system. The max output setting allows for a current or power limit that keeps the output operating within the voltage compliance limit to ensure the best possible resolution. These parameters work with the Heater Range parameter range to provide safety and flexibility across up to 100 W and 1 W max outputs.

While operating the outputs on a 346 in closed loop control, three major components are necessary. First, an input must be selected to operate on and depending on whether or not a curve is applied, will use either the sensor reading (without a curve), or temperature reading (with a curve). Second, a setpoint matching the units provided by the input is chosen to calculate error. Finally, gains of P, I, and D are used to convert the calculated error to heater power.

If any of these three parts of an output are changed, it is possible that it could have effects on the others. For example, changing the input can reset the setpoint if the units do not match. This is to prevent changing from setpoints in ohms (usually in the 10 Ω to 100 kΩ range) to a setpoint in volts (-50 mV to 2.5 V range). Other changes include:

Applying or removing a curve to an input
Applying the input to another output
Applying a new input to the output

OUTGROUP Output Heater Group Command

OUTGROUP <output>, <group>

Parameters

Name	Type	Description
output	n	The heater number to configure: 1 to 4
group	n	The heater group to assign the output to: 9 or 10; 0 = do not assign output to a group

Example

OUTGROUP 2,9[term]

Heater output 2 will be assigned to heater group 9.

Remarks

The OUTGROUP command allows for the grouping of heater outputs for coordinated control. This can be useful for applications where multiple heaters need to be controlled together, such as in a stage where multiple heaters are required to control at a power greater than 100 W. When outputs are grouped, they will share the same control parameters (P, I, D, Setpoint, Ramp Rate) and will be controlled as a single entity. The power output of each heater in the group will be adjusted proportionally based on their individual HTRSET max power settings and will output power according to the OUTMODE setting of the heater group channel.

If any individual heater in a group has a fault condition (short/open), the entire group will be disabled to ensure safety. The group will remain disabled until the fault condition is cleared and the heaters are manually re-enabled.

When using heater groups, it is important to ensure that all physical heaters in the group are configured correctly and that their respective HTRSET parameters are set appropriately for the desired control behavior. In addition, once a heater output is assigned to a heater group, its output mode settings (OUTMODE) cannot be configured individually, and any attempt to do so will result in an error (-203 command protected).

OUTGROUP? Output Heater Group Query

OUTGROUP? <output> [term]

Parameters

Name	Type	Description
output	n	The heater number to query: 1 to 4

Returns

<group> [term] (see command for description)

OUTMODE Output Mode Command

OUTMODE <output>, <mode>, <input>, <powerup enable>, <warmup> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10
mode	n	Specifies the control mode. Valid entries: 0 = Off 1 = Closed Loop PID 2 = Zone 3 = Open Loop 4 = Monitor Out
input	a	Specifies input to use for control: A, B, C1, C2, C3, C4, D1, D2, D3, D4, E1, E2, E3, E4, F1, F2, F3, F4, G1, G2, G3, G4, H1, H2, H3, H4, NONE
powerup enable	n	Specifies whether the output restarts or remains off after power cycle. Valid entries: 0 = Powerup enable off 1 = Powerup enable on
warmup	n	Specifies if the output will be used for warmup. Valid entries: 0 = Off 1 = On

Example

OUTMODE 1,1,A,0,0[term]

Output 1 is configured for closed-loop control mode, using Input A

Remarks

Monitor out mode is only valid for analog outputs 5 to 8. Zone and warmup is only valid for heater outputs 1 to 4, and heater groups 9 and 10. None can be used for open-loop control. In addition, none will be assigned automatically if an output’s prior input was assigned to another output. For example: OUTMODE 1,1,A,0,0; followed by OUTMODE 2,1,A,0,0; will result in output 1 being assigned to NONE. Closed-loop mode will not allow the range to be set if the input is NONE.

OUTMODE? Output Mode Query

OUTMODE? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<mode>, <input>, <powerup enable>, <warmup> [term] (see command for description)

HTRSET Heater Setup Command

HTRSET <output>, <resistance>, <max output>, <current/power>[term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 4, 9 or 10
resistance	nnn	Specifies the resistance of the heater load in ohms. 10 Ω to 100 Ω (25 Ω default)
max output	+n.nnn	Represents 100% output as either power or current depending on the <current/power> setting on HIGH range.
current/power	n	Specifies whether the max output is in current or power. Valid entries: 0 = Power 1 = Current

Example

HTRSET 2, 25, 40, 0[term]

Heater output 2 will be configured to know that a 25 Ω heater is attached and the 346 heater output will treat 100% out as 4 W.

Remarks

The current/power parameter determines how the output percentage is applied to the heater. When in units of current, the heater output percentage is a percentage of the full-scale current, as specified in the max output parameter. When in units of power, the output percentage is a percentage of full-scale power, also specified by the max output parameter.

For example, if the full-scale output is 100 W and in power mode and 50% output is requested, the internal current source will provide 1.41 A to your 25 Ω load for a total of 50 W.

It should also be noted that this max output value is applicable only for the HIGH heater range. If the low range is selected, the Model 346 automatically scales down the max output setting accordingly. For example, in power mode, if the max output is set to 50 W, then 50 W will be the maximum output when the HIGH range is selected, while the LOW range maximum output will be 500 mW, since the LOW range hardware is designed to output 1/100th of the HIGH range power. The same idea applies to current. If the max output is set to 1 A, then 1 A will be used for the HIGH range max output, while 100 mA will be used for the low range, since the LOW range hardware is designed to output 1/10th of the HIGH range current.

For use with heater groups (9 and 10), the max output parameter and resistance parameter are unused, as the physical channels are used to determine the max output and resistance of their respective heater loads. Because of this, valid entries must be provided, but are recommended to be set to 25 Ω and 100 W.

Note, if the value provided in max output exceeds the current/power hardware limits of the output, based on the resistance, the instrument will adjust the max output accordingly. For example, a command of HTRSET 1, 50, 100, 0 will cause the instrumetn to only be able to output 50 W max across a 50 Ω load)

HTRSET? Heater Setup Query

HTRSET? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 4, 9 or 10

Returns

<resistance>, <max output>, <current/power> [term] (see command for description)

Remarks

As mentioned in the HTRSET command description, the instrument will limit max output if a max current/power value exceeds the hardware limits, for a given heater resistance. The max output query will return the actual max output being applied.

HTRLIM Heater Short/Open Command

HTRLIM <output>, <enabled>, <short resistance>, <open resistance> [term]

Parameters

Name	Type	Description
output	n	The heater number to configure: 1 to 4
enabled	n	Configures if a detected short or open will shut off the heater (On = 1), or will be ignored (Off = 0)
short resistance	+nnn.n	Resistances below this value are a short
open resistance	+nnn.n	Resistances above this value are an open

Example

HTRLIM 3, 1, 25, 250[term]

Heater output 3 will have short/open protection enabled with a short circuit being any measured heater resistance below 25 Ω and an open circuit being any measured heater resistance above 250Ω.

Remarks

To ensure as few false positives as possible, a short or open condition must be present for at least 5 s before shutting off the heaters. The heater must also be outputting at least 10% of full scale to get an accurate reading of the heater load’s resistance. If the output percentage is less than 10%, then the heater limits are not checked nor enforced.

HTRLIM? Heater Short/Open Query

HTRLIM? <output> [term]

Parameters

Name	Type	Description
output	n	The heater number to configure: 1 to 4

Returns

<enabled>, <short resistance>, <open resistance> [term] (see command for description)

RANGE Heater Range Command

RANGE <output>, <range> [term]

Parameters

Name

Type

Description

output

n

The output number to configure: 1 to 10

range

n

For heater outputs 1 - 4, and heater groups 9 and 10:

0 = Off

1 = Low

2 = High

For analog out outputs 5 - 8:

0 = Off

1 = On

Example

RANGE 2,2[term]

Heater output 2 will be configured to the high range.

Remarks

For heater outputs 1 to 4 and heater groups 9 and 10, the HIGH setting provides the maximum amount of output power, while the low setting provides a full-scale output range of 1/100th of maximum power. From a current perspective, the HIGH setting causes the output to have a full scale output of 2 A, while the LOW setting causes the output to have a full scale output of 200 mA Full scale current/power is determined by the HTRSET command settings.

Note, for the heaters, the OFF range disables the heater by shorting the heater leads together and floating them from the heater circuit. This is the fallback state an output enters if it detects fault conditions.

RANGE? Heater Range Query

RANGE? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<range> [term] (see command for description)

HTRAUTO Heater Autorange Command

HTRAUTO <output>, <autorange> [term]

Parameters

Name

Type

Description

output

n

The output number to configure: 1 to 4, 9 or 10

autorange

n

For heater outputs 1 to 4, 9 or 10

0 = Disabled

1 = Enabled

Example

HTRAUTO 2,1[term]

Heater output 2 will be configured to autorange.

Remarks

This feature is designed to be used with PID gains configured for the high range, and automatically swaps the heater range between high and low based on the output percentage. When enabled, if the output percentage drops below 8% of current or .8% of power the range will switch to low. If the output percentage goes above 10% of current or 1% of power, the range will switch to high.

This command works together with the RANGE command. The RANGE command is used to de-energize the heaters to OFF. It is also used to energize the heater by setting it to an initial range. When heater autorange is enabled, the Model 346 will automatically adjust the range to either HIGH or LOW as necessary.

HTRAUTO? Heater Autorange Query

HTRAUTO? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 4, 9 or 10

Returns

<autorange> [term] (see command for description)

HTR? Heater Percentage Query

HTR? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<output percentage> [term]

Remarks

Returns the present heater percentage of full scale for the output. This can be converted into output power or current by using the HTRSET parameters for outputs 1 to 4, or by multiplying by 10 V on outputs 5 to 8. This is the theoretical value and may not reflect the actual output due to load conditions, incorrectly entered HTRSET resistance, or other factors.

AOUT? Analog Output Data Query

AOUT? <output> [term]

Remarks

This is a query available on the Model 336. Because the Model 346 considers outputs 5 to 8 auxiliary 1 W heaters, the AOUT? query is not implemented. To retrieve the output percentage for analog outputs 5 to 8, use the HTR? query.

HTROUT? Heater Output Query

HTROUT? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<output value>, <output power> [term]

Remarks

Returns the calculated output value and power for the specified output. For outputs 1 to 4, the output value is the calculated output current in Amperes, while for outputs 5 to 8, the output value is the calculated output voltage in Volts. The power value is calculated as follows:

Outputs 1 to 4: Power (W) = (output current (A)) ² × heater resistance (Ω)

Outputs 5 to 8: Power is not calculated and will return 0.0

For heater groups 9 and 10, the output value is the sum of the output currents of the physical heater outputs in the group, and the power is the sum of their calculated powers.

HTRDIAG? Heater Output Measurement Query

HTRDIAG? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 8

Returns

<voltage>,<current>,<resistance>,<power> [term]

Remarks

These readings are purely for diagnostic purposes and do not have any associated accuracy specifications. Typically, one can expect accuracies in the 3 to 5% range, down to about 10% of the output of the heater (1 to 4) or the analog output (5 to 8). Below 10% of output percentage, the readings are highly inaccurate. Note, for the analog outputs 5 to 8, the voltage is not measured, so the value returned in this query is simply the commanded output voltage. For example, if the analog output is overloaded, the voltage will still return what is being commanded, not the actual reduced voltage output as a result of the short. The resistance and power values are simply calculated as a result of the measured voltages and currents. In addition, the voltages and currents measured (and the subsequent power and resistance calculations) are from the perspective of the internal circuitry, and don’t account for any losses outside of the instrument (for example, voltage drops due to lead resistnace). The readings of heaters 1 to 4 are updated every 100 ms, while the analog outputs 5 to 8 are updated every 250 ms.

MOUT Manual Output Command

MOUT <output>, <percentage> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10
percentage	+nnn	The percentage of full scale output. 0 to 100

Example

MOUT 1,22.45[term]

Sets output 1 manual output percentage to 22.45%.

Remarks

What the percentage represents is a function of the current/power and max output settings as specified in the HTRSET command. When in units of current, the output percentage is a percentage of the full scale max output specified. When in units of power, the output percentage is full scale power, with full scale power being defined as (max current output)² × heater resistance.

Manual output does not apply in OFF mode

MOUT? Manual Output Query

MOUT? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<percentage> [term] (see command for description)

OUTLIMIT Output Percentage Limit Command

OUTLIMIT <output>, <max percentage> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10
max percentage	+nnn	The maximum output percentage limit. 0 to 100

Example

OUTLIMIT 1,75[term]

Sets output 1 maximum output percentage limit to 75%.

Remarks

This feature is designed to limit the maximum output percentage of an output. When a limit is set, any command or control loop that attempts to drive the output will be limited to this value, and if the value would be exceeded, a status bit will be set in OUTST? to indicate the output is being limited.

OUTLIMIT? Output Percentage Limit Query

OUTLIMIT? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<max percentage> [term] (see command for description)

PID Control Loop PID Values Command

PID <output>, <P>, <I>, <D> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10.
P	+nnn	The proportional gain value. 0.1 to 100,000.
I	+nnn	The integral gain value. 0.1 to 100,000.
D	+nnn	The derivative gain value. 0 to 20,000.

Example

PID 1,10,50,0[term]

sets the PID values for output 1 where P is 10, I is 50, and D is 0%

Remarks

Control settings, (P, I, D, and Setpoint) are assigned to outputs, which results in the settings being applied to any loop formed by the output and its control input. Note the I term is internally scaled by the P, and the D value is called by both I and P. This means, you must have a P term entered to use I, and you must have P and I terms entered to use D.

PID? Control Loop PID Values Query

PID? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<P>, <I>, <D> [term] (see command for description)

SETP Control Setpoint Command

SETP <output>, <setpoint> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10
setpoint	+nnn.n	The value for the setpoint, in either units of sensor or temperature (see remarks)

Example

SETP 1,122.5[term]

sets the setpoint for output 1 to 122.5, based on the units of the input that output 1 is tied to.

Remarks

Control settings, that is, P, I, D, and Setpoint, are assigned to outputs, which results in the settings being applied to the control loop formed by the output and its control input. Regarding the units of this setpoint value, if a curve is not assigned to an input, the setpoint will be in sensor units. When a curve is assigned to an input, this causes the instrument to interpret this setpoint in temperature units of either Kelvin or Celsius, as specified in the INTYPE command. For information regarding assigning curves, see the INCRV command.

SETP? Control Setpoint Query

SETP? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<setpoint> [term] (see command for description)

Remarks

Note, if setpoint ramping is enabled and the setpoint is actively ramping, this query returns a ‘real-time’ sample of wherever the setpoint is in the ramping process, at the moment the query is issued. Otherwise, the query returns the static setpoint setting. When ramping, this setpoint query has an update rate of 10 Hz.

SETPRST Control Setpoint Reset Command

SETPRST <output> [term]

Parameters

Name	Type	Description
output	n	The output number to reset: 1 to 10

Example

SETPRST 1[term]

Resets the setpoint for output 1 to the current input reading value.

Remarks

This command is used for quickly snapping a setpoint while ramping, or for convenience when the setpoint is desired to be the same as the input value. However, if the current output has no attached input (ie. OUTMODE 1,3,NONE,0), the setpoint will be set to 0.

RAMP Setpoint Ramp Command

RAMP <output>, <enable>, <rate> [term]

Parameters

Name

Type

Description

output

n

The output number to configure: 1 to 10

enable

n

Specifies if the ramp rate is enabled. Valid entries:

0 = Off

1 = On

rate

+nn.n

Ramp rate in K/min. 0.1 to 100 (0 disables ramping).

Example

RAMP 1,1,10.0[term]

Sets the ramp rate for output 1 to 10 K/min and enables ramping.

Remarks

Disabling the ramp rate will cause the setpoint to jump to any new setpoint instantly, and if the Model 346 was previously ramping, it will complete its ramp instantly. In addition, a transition to disabled causes PID state variables, such as the I accumulator and the D term, to reset, as this is considered a step change in the setpoint. A ramp rate of 0 K/min can be applied, however this simply responds as if ramping was off. This has some automation uses in zone operation, but is not recommended for general use.

RAMP? Setpoint Ramp Query

RAMP? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<enable>, <rate> [term] (see command for description)

RAMPSETP? Ramp Setpoint Query

RAMPSETP? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<setpoint> [term]

Remarks

This command will return the setpoint that the output is ramping to, or if the output is not ramping, it will return the current setpoint. This query is available since, when ramping, the SETP? query will return a real-time snapshot of wherever the setpoint is in the ramp cycle, at the moment the query is issued.

RAMPST? Setpoint Ramp Status Query

RAMPST? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<status> [term]

Name	Type	Description
status	n	0 = not ramping, 1 = ramping

Remarks

This query will report whether the specified output’s setpoint is actively ramping or not.

ZONE Zone Settings Command

ZONE <output>, <zone>, <upper boundary>, <kp>, <ki>, <kd>, <mout>, <output limit>, <range>, <input>, <ramp rate> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 4, 9 or 10
zone	n	The zone number to configure: 1 to 10
upper boundary	+nnn.n	The upper boundary of the zone in Kelvin
kp	+nnn	The proportional gain value. 0.1 to 100,000.
ki	+nnn	The integral gain value. 0.1 to 100,000.
kd	+nnn	The derivative gain value. 0 to 20,000.
mout	+nnn	The manual output percentage. 0 to 100.
output limit	+nnn	The output limit percentage. 0 to 100.
range	n	The heater range. Valid entries: 0 = Off 1 = Low 2 = High
input	a	Specifies input to use for control: A, B, C1, C2, C3, C4, D1, D2, D3, D4, E1, E2, E3, E4, F1, F2, F3, F4, G1, G2, G3, G4, H1, H2, H3, H4
ramp rate	+nn.n	Ramp rate in K/min. 0.1 to 100 (0 disables ramping)

Example

ZONE 1,1,300,10,50,0,0,100,2,A,10.0[term]

Sets the zone settings for output 1, zone 1, with an upper boundary of 300 K, a P term of 10, I term of 50, D term of 0, manual output of 0%, output limit of 100%, high range, input A, and a ramp rate of 10 K/min.

Remarks

Zones are defined by upper bounds with the first zone having an implied lower bound of 0 K. Zones are used to define different control parameters for different temperature ranges and can also be used for automation when combined with ramping. Zones are not compatible with analog outputs 5 to 8.

ZONE? Zone Settings Query

ZONE? <output>, <zone> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 4, 9, or 10
zone	n	The zone number to query: 1 to 10

Returns

<upper boundary>, <kp>, <ki>, <kd>, <mout>, <output limit>, <range>, <input>, <ramp rate> [term] (see command for description)

ANALOG Monitor Out Parameter Command

ANALOG <output>, <high value>, <low value> [term]

Parameters

Name	Type	Description
output	n	The output number to configure: 5 to 8
high value	+nnnnn	The input reading at which the analog output reaches 100% output (+10 V).
low value	+nnnnn	The input reading at which the analog output is 0% output (0 V).

Example

ANALOG 5,100.0,20[term]

Sets the monitor out parameters for output 5 where the high value is 100.0 and the low value is 20.0.

Remarks

The input reading that the analog output monitors is specified by using the OUTMODE command, which allows the tying of an output to an input.

The units of the high value and low value are dependent of if a curve is assigned to the specified input. If a curve is not assigned to the specified input, the high and low values will be in sensor units. When a curve is assigned to an input, this causes the instrument to interpret the high and low values in temperature units, as specified in the INTYPE command. To assign a curve to an input, see the INCRV command. In the example above, it’s assumed a curve is assigned to the input tied to output 5. Is also assumes the units are Kelvin, as specified by the INTYPE command.

ANALOG? Monitor Out Parameter Query

ANALOG? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 5 to 8

Returns

<high value>, <low value> [term] (see command for description)

OUTSTABLE Output Control Stability Command

OUTSTABLE <output>, <enabled>, <setpoint error>, <settle time>, <audible>, <visible>[term]

Parameters

Name	Type	Description
output	n	The output number to configure: 1 to 10
enabled	n	Specifies if stability detection is enabled. Valid entries: 0 = Off 1 = On
setpoint error	+nn.n	The maximum allowable error from the setpoint in K.
settle time	n.nnn	The amount of time in seconds the output must remain within the setpoint error and stabilizing to be considered stable.
audible	n	Specifies if an audible tone sounds when stability is achieved. Valid entries: 0 = Off 1 = On
visible	n	Specifies if a chip is displayed on an output card when stability is achieved. Valid entries: 0 = Off 1 = On

Example

OUTSTABLE 1,1,0.5,30,1,1[term] Enables stability detection for output 1 with a setpoint error of 0.5 K, a settle time of 30 s, audible tone enabled, and visible indicator enabled.

Remarks

The output control stability command is used to configure stability detection parameters for a given PID control loop. When enabled, information about the PID control loop will be monitored for stability based on the provided parameters, once the sensor reading has achieved two local maximums above the setpoint, but still in-band, and two local minimums below the setpoint, but still in band, then the output will be considered stabilizing. After the settle time has passed without the input reading leaving the band, it will be considered stable. When stability is achieved, the STABLE bit will be set in the OUTOPR? status query, and any relays tied using the STABILITY mode will activate.

OUTSTABLE? Output Control Stability Query

OUTSTABLE? <output> [term]

Parameters

Name	Type	Description
output	n	The output number to query: 1 to 10

Returns

<enabled>, <setpoint error>, <settle time>, <audible>, <visible> [term] (see command for description)

WARM Warmup Command

WARM <temperature>, <percentage> [term]

Parameters

Name	Type	Description
temperature	+n.nn	The target temperature for the warmup process. Valid entries of 275 K to 325 K
percentage	+nn.n	The acceptable output level for the system to be considered WARM. 0 to 100%

Example

WARM 300, 5[term]

Initiates a warmup to 300 K, which will be consdered WARM at output values below 5%

Remarks

The warmup command is used to set a target temperature for the warmup process. All warmup-enabled outputs will have their setpoints set to this temperature, without ramping, and at a range of high. Upon commencement of the warmup, the warming status bit (bit 6) of the output operation register (OUTOPR?) will be set.

When a output with the warming status bit set reaches above its setpoint and is outputting less than the specified percentage, the warm status bit (bit 7) will be set). When all warming outputs also have their warm bits set, the warmup is completed and a dialog will be displayed on the front panel prompting the user to either turn off all outputs or continue controlling.