13 | © Frio 2021 - Rev. 0.3 - Updated 3/2/2021
3.5.2
Sensor Failure
The sensor failure alarm is a critical alarm that is enabled if the device is in a control mode that relies on a local
temperature sensor. If the sensor fails, the device will go into the failure state. To configure the failure state, select
Settings
from the
Main Menu
, then select
Failure State
from the
Settings Menu
. The failure state may be set to ON
or OFF. The default setting for the failure state is ON. If the sensor returns to normal operation, the system will revert
from the failure state and resume using the sensor for control. However, the sensor failure alarm is latching, so the
alarm will remain present until it is reset via the HMI.
3.5.3
GFEP Alarms
The GFEP system will alarm and activate the dry contact when the ground fault current exceeds the GFEP Trip Level,
which will automatically shut off the heating system. The GFEP alarm is a critical alarm that is latching and must be
reset by the user via the HMI. The device will automatically run a GFEP test and must pass in order to clear a GFEP
alarm.
When this device is in fire protection mode, the system will not turn off the heating system when the ground fault
current exceeds the GFEP Trip Level, but the system will still activate the GFEP alarm and the alarm dry contact. In
this case, the GFEP alarm will be latching and must be cleared via the HMI.
3.5.4
Active Alarms
Active alarms can be viewed from the HMI by selecting
Active Alarms
from the
Main Menu
. The active alarm page
on will display all active alarms. The user may select an alarm to view:
Duration
(the time since the alarm condition
started),
Returned?
(whether the alarm condition ceased/returned to normal).
To reset the alarms, select
Active Alarms
from the
Main Menu
, then select
Reset All
. You will then be prompted to
Test/Reset Now
, select
Yes
to initiate a GFEP test and reset the alarm conditions. The GFEP test must be successful
in order to reset the alarms.
3.6
S
ENSORS
The Frio S1 device includes internal sensors that monitor supply voltage, operating current, and ground fault current.
Information from these sensors is used for control of the system, system monitoring, alarms, and GFEP. The Frio S1
also includes two optional external temperature sensors: an RTD and a thermistor.
3.6.1
RTD
The Frio S1 is compatible with all 3 wire pt100 RTDs. RTD lead wires must be 18-24 AWG shielded twisted pair.
3.6.2
Thermistor
The Frio S1 should only be used with the Frio thermistor. The Frio thermistor is a 10k NTC thermistor with ± 1%
accuracy. The Frio thermistor has an operating range of -40°C to 105°C and an international protection rating of IP68.
The Frio thermistor is RoHS Compatible Thermistors. Each Frio thermistor comes with 2m leads, which may be
extended as required using twisted shielded pair 24 AWG wire. The lead wire is black TPE, and the thermistor tip is
encapsulated using black TPE.