Pentair 920 Series - TS Fail Mode and Sensor Control Modes

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EN- Raychem920series-IM-H5687405/15
INDUSTRIAL HEAT TRACING SOLUTIONS
Range: 0.3 to 100.0 amps
(CURRENT TURNS RATIO = 1.00)
Procedure: Adjust the CIRCUIT BREAKER CURRENT RATING setting to the heating circuit breaker
size (i.e. 30.0 amps). Note that the CIRCUIT BREAKER CURRENT RATING setting is affected by the
CURRENT TURNS RATIO setting. The absolute maximum adjusted CIRCUIT BREAKER CURRENT
RATING setting is 300.0 amps. The absolute minimum adjusted CIRCUIT BREAKER CURRENT
RATING setting is 0.1 amps. See section 3.5.22 on page 26 for more information regarding the
CURRENT TURNS RATIO function.
IMPORTANT: This feature should not be used to reduce the size of a circuit breaker or increase
the maximum heating cable length. It can be quite effective in preventing nuisance trips due to
incorrect design or factors outside those considered by the design.
3.5.9 MAXIMUM POWER SETTING (SSR ONLY)
Purpose: This user-selectable level limits the maximum amount of power applied to a heat
trace circuit. This is an average power calculated by the controller using the average current
and applied voltage. The HTC switches the output on and off rapidly to limit the average current
to an appropriate level. The MAXIMUM POWER level may be adjusted to eliminate step-down
transformers, lower the effective output wattage of a cable, or implement energy management of
the heat trace circuit.
Range: 3 to 33,000 Watts
(VOLTAGE and CURRENT TURNS RATIOS = 1.00)
Procedure: Adjust the MAXIMUM POWER level to the desired value (watts). Use the TEST TRACING
function to observe the power limiting oper-ation.
IMPORTANT:
• Thisfunctionmaybesetwithinreasonablelimitsfortheparticulartracerbeingpowered.The
effective resolution of the setting is limited to 1/30th of the calculated full on power.
• DonotsettheMAXIMUMPOWERbelowfulloutputforapplicationsthatdonotrequirecontrol
of power.
• ThisfeatureisaffectedbytheVOLTAGEandCURRENTTURNSRATIOsettings.Themaximum
range using adjusted values of voltage and current is 65,535 watts. See sections 3.5.21 on page
26 and 3.5.22 on page 26 for more information regarding the turns ratio functions.
3.5.10 3-PHASE POWER CALCULATION (V3.11 AND UP)
Purpose: This parameter selects the type of power calculation that the HTC is to perform.
Setting:NOorYES
Procedure:Ifanautomatic3-phasepowercalculationisdesired,selectYES.Ifanormalpower
calculation is desired, select NO.
IMPORTANT: For the total 3-phase power calculation to be accurate the following conditions must
be met:
• Allthreephasesmustbebalancedandstar(“Y”)connected
• Themeasuredcorrectedcurrentisoneofthephasecurrents
• Themeasuredcorrectedvoltageisthelinetolinevoltage
The formula used to calculate this total power is: P
total
= √3 x I
phase
x V
line-line
3.5.11 TS FAIL MODE (V3.11 AND UP)
Purpose: This parameter determines whether the HTC turns the output switch ON or OFF if all
selected temperature sensors fail to provide a control temperature.
Setting: OFF or ON
Procedure: If the HTC should turn the output switch off when it cannot read a valid control
temperature,thenselectOFF;otherwise,iftheoutputswitchshouldturnon,thenselectON.
IMPORTANT: This parameter is part of the TS CONTROL MODE.