Nextron MASTERTRACE MS-2102, Руководство оператора

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3.4
MS-2102 Chapter 3 Getting Started
4. Press [STORE] to save the value.
5. With the heater forced on, verify that the expected
current is flowing using the actual current message,
located in ACTUAL\OPERATING VALUES\HEATER
CURRENT. You can use a clamp-on ammeter attached
to one of the heater wires to compare readings. With
proportional control selected, the readings may differ
due to harmonics in the current waveform.
Testing Alarms: The manual alarm setpoint works exactly
like the manual heaters setpoint except that it energizes
the output alarm and indicator. This setpoint is useful for
commissioning a new system or checking alarm circuits.
Normally this setpoint will be DISABLED.
Monitoring System Status
Now that the MS-2102 controller has been programmed
for a specific application, you can check system status. If
no keys are pressed for the time specified in DISPLAY
TIMEOUT message located in SETPOINT\SYSTEM
SETUP\DISPLAY TIMEOUT, the display will automati-
cally go into the default message mode. System Status
mode is recommended; that is, the display will automati-
cally display all alarms. If desired, you can change this to
a specific message later by reprogramming the default
message.
Access actual values by pressing [MEASURED]. These
are divided into 2 groups. Pressing [MEASURED] once
accesses the group of messages that show current values
of temperature, current, etc. Pressing [MEASURED]
twice displays the statistics data such as minimum/
maximum temperature, power consumption, running
hours etc. Unlike setpoints, you cannot change actual
values using [VALUE
ñ
] , [VALUE
ò
] or [STORE].
There is a summary of all Measured Values messages at
the beginning of Chapter 5 Measured Values.
To view the actual values,
1. Press [MEASURED].
2. Press [MESSAGE
ò
] to view each actual value.
3. Continue examining each value of interest by pressing
the [MESSAGE
ò
] key and referring to Chapter 5
Actual Values.
Monitoring Heater Temperature
To monitor the heater temperature,
1. Press [MEASURED] once to display:
HEATER CONTROL TEMP:
55 °C
This is the temperature value that the controller will use
with the heater setpoint to determine the heater output.
The 2 heaters in MS-2102 use the actual temperatures of
RTD1 & RTD2 as their control temperatures, respectively.
If no RTD sensor is connected or a lead is broken the
value RTD OPEN appears. This is an alarm condition.
When the temperature falls below the heater setpoint, 50
°C in our example, heater 2 in the MS2102 switches on to
supply power to the heater circuit. It stays on until the
temperature rises above the heater setpoint (50 °C). Once
the system has been running for a few hours, the heater
temperature should be at or above this setpoint value.
If hot fluid is being pumped through the pipe, the meas-
ured temperature may be much higher than the setpoint
temperature. But in this case, no power should be sup-
plied to the heater and the HEATER ON indicator will
be off.
If the heater temperature is less than the minimum display
value (-50 °C/-58 °F), the word RTD SHORT appears. If
the temperature is over the maximum value (+ 500 °C / 932
°F), the word RTD OPEN appears. If an abnormal value
appears, particularly on a new installation, check that the
correct RTD sensor type has been installed (100 OHM
platinum DIN 43760) and that the three RTD wires are
wired to the correct terminals.
Monitoring Actual Current:
To monitor the actual current,
1. Press [MEASURED].
2. Press [MESSAGE
ò
] 5 times to display:
HEATER CURRENT
5.5 A
This value is the actual measured current of the heater.
Resolution is to 0.1 amp over a range of 0.0 to 30.0 amps.
Above 30.0 amps the value displayed reads O.L
(Overload).
With MI (Mineral Insulated) cable used in this example, it
will either be 0.0 if the heater is not energized or a fairly
constant current such as 5.0 amps.
Monitoring Ground Fault Current:
Some stray current always flows to ground due to
capacitance effects and leakage.
To monitor ground fault current,
1. Press the [MESSAGE
ò
] key from the heater voltage
message
or