TRACE
MATE II-CTR Chapter 4
Operation
4.1
Alarms
There are totally5 types of alarm in TraceMate II-CTR.
They are listed below.
RTD Fail: If theRTD sensor is notconnected or shorted,
an RTD Fail alarm occurs. Check that the RTD sensor is
properlyconnected. This alarm is not latched and will be
reset as soon as the RTD is properly connected. In the
event ofan RTD failure, the heater output is turned off to
prevent a runaway heating situation.
LowTemperature: Once the actual temperature is below
the low temperature alarm setpoint, a LowTemperature
alarm occurs.This will normallyindicate that theheater
circuitisnot providing enough heat tomaintain the
setpoint. When a system is first turned on this alarm may
be activated. It is particularlyuseful in taking corrective
action in freezeprotection systems to prevent a burst
pipe.This alarm is not latched and will be reset as soon as
thealarm conditiondisappears.
High Temperature: Once the actual temperature is above
the high temperaturealarm setpoint, High Temperature
alarm occurs. Thisalarm is not latched and will be reset
as soon as the alarm condition disappears.
Current Fail: This alarm is activated when a heater in
TraceMate II-CTR calls for heatbut the actual current is
lessthan the current fail alarm setpoint. Either the
continuityofthe wiring andheat tracing cableis defective
or a very small heater is being switched. In order to detect
faultson dormant systemswith theTraceCheck feature,
which turns on the heaters for 20 seconds every24 hours,
this alarm is latched. Thus, once the condition is detected,
thealarm will remain on until reset.
Ground Fault Trip:This alarm is activated when the
groundfault current is abovethegroundfault tripalarm
setpoint. Aground fault is a current toground caused by
moisture, corrosion or insulation breakdown. Often the
amount ofgroundfault current is not enough to trip the
heater circuit breaker but could result in a serious fire
hazard, especiallywith self-regulatingcable. When a
ground fault is detected, the heater will be switched off,
even if the control is calling for heat. This eliminates the
need for an expensiveground fault circuit breaker. Large
ground fault currents will trip the heater circuit breaker,
so an intentional time delay is allowed for the breaker to
clear high fault currents, which can occur on solidly
grounded systems.
Since a heater may be shut off after a ground fault, it is
veryimportant that the alarm outputs be used so
corrective action can be taken quicklyenough to prevent
a process shutdown due to the loss of heat to a pipe.
Ground fault detection only works with resistance or
solidlygrounded systems. Ifthe system is ungrounded, it
must begrounded or an artificial ground must be created
bymeans of a zip-zagtransformer. Once a ground fault
condition is detected, it remainslatched until it is reset.
Alarm Contacts
When an alarm occurs, the two alarmcontacts are
activated. Since both these contacts are configured as
normallyclosed, the impedances across terminal 10 & 11
and terminal 12 & 13 both increasesignificantly. The
From C alarm drycontact reacts to the alarm/nopower
situation like this: Terminal 21 &22 become closed and
terminal 22 & 23 become open.
Alarm Messages
When an alarm condition occurs on a particular heater , a
corresponding alarm message will be shown on the LCD
to provide a fast fault diagnosis.
For an RTD fail alarm on heater x, the alarm messageis
“RTD Fail on HTRx”.
For a lowtemperature alarm on heater x, the alarm
message is “LT Alarm on HTRx”.
For a high temperature alarm on heater x,thealarm
message is “HTAlarm onHTRx”.
For a current failalarm on heater x, the alarm message is
“AMP Fail on HTRx”.
For a ground fault trip alarm on heater x, the alarm
message is “GFAlarm onHTRx”.
Alarm Indicators
There are 5 alarm indicators on the control board of the
TraceMate II-CTR.Theyare used to indicatethe alarm
conditions for a particular heater selected by S12, refer to
Figure 2.1.
RTD Fail Indicator:When an RTD Fail alarm condition
occurs on the selected heater, the red RTD FAIL indicator
LED will be on.
LowTemperatureIndicator:When a low temperature
alarm condition occurs on the selected heater, the red LO
TEMP indicator LED will be on.
HighTemperature Indicator: When a high temperature
alarm condition occurs on the selected heater, the red HT
TEMP indicator LED will be on.
Current Fail Indicator:When a currentfail alarm
condition occurs on the selected heater, the red AMP
FAILindicator LED will be on.
GroundFaultTripIndicator: When a ground fault trip
alarm condition occurs on the selected heater, the red GF
indicator LED will be on.
StatusIndicators
Power On Indicator: The control power for the
TraceMate II-CTR comes from heater 1’s power inputs (
terminal 1 & 2 ). When the control power is applied tothe
TraceMate II-CTR, the green PWR ON indicator LED
should be on. If this LED is not on, check that the
appropriate voltage is present byconnecting a meter
across terminals 1 and 2. If voltage is present and the
LED is off, the control board should be replaced and sent
