Hoffman Controls Model 610 Series - Compressor Temperature Sensing Information; Exhaust Temperature Sensor Installation

12
Normal Operation Con't
Phase imbalance and phase order trips do not occur until
the trip situation has existed for the minimum time selected in
the "
Phase Imbalance Delay
" menu,
to allow the 2
nd
the trip situation has existed for the minimum time selected in
nd
the trip situation has existed for the minimum time selected in
winding,
on a part (split) winding motor application, to power up
.
(see
"
Sequence of Operation
" section, number "
7
", on page 17 for the
details)
If an exh
aust temperature or oil temperature sensor is being used
and the Model 610 detects a bad temperature reading,
a trip occurs
and
E
XHAUST
EXHAUSTE
_BAD
or
OIL
_BAD
OIL_BADOIL
is displayed on the LCD's
screen.
Temperature trips, due to out of range sensor temperatures
(either below a low temperature trip value or above a high temper-
ature trip
value)
occur immediately when the sensed temperature
reaches the trip value.
When a temperature trip occurs that will be automatically reset,
the LCD displays the type of trip (
EXHAUST
or
OIL
) and the
time in minutes until that trip will be reset automatically. If desired
the operator can manually reset the trip, during this automatic
reset time, by pressing and releasing the
MODE
button until the
MODE button until the MODE
LCD screen displays the "
For Manual Reset Press Enter
" message
and then pressing the
ENTER
button once.
ENTER button once.ENTER
If the controller has the Modbus option, then a command to
manually reset the controller,
as well as a command to
trip the
controller, can be sent remotely over the Modbus RTU connection
using address registers 16 and 18 respectively.
The operator can always check the trip level values and all the
other Model 610 Digital Current Monitor's parameters, by using
the menu system as described in the "
Sequence of
Operation"
section (pages 16 thru 19) or using the Modbus RTU connection
to read the Model 610's internal register data, using the
TABLE
6A
and
6B
information on pages 13
& 1
4
.
A
Model 610 Menu System Flow
Chart
Model 610 Menu System Flow ChartModel 610 Menu System Flow
(
Chart ( Chart
Figure
6
, pages 10 &
11)
is provided to allow the operator to track his/her progress
thru
the
various
LCD's screens.
The Menu System Flow Chart's infor-
mation is viewed starting from the Home Screen, located at the
top center
of the chart, and continuing counter clockwise around
the chart.
NOTE:
The
Model 610 Menu System Flow
Chart
informa-
tion is pre
sented in the same mode, menu and submenu order
as
the
information pre
sented on the
LCD
screen, when following the
chart's information in a
counter clockwise
direction
.
The Model 610 Digital Current Monitor is designed to work
with virtually all thermistor type temperature sensors. However,
due to the many differences in compressor types and sizes along
with the large availability of Omega thermistor temperature
sensors, Hoffman Controls does not offer a temperature sensor as
an option for the Model 610
Digital Current Monitor
.
T
he Omega Company manufactures a readily
available variety of
R - T
(resistance - temperature) sensors with
different temperature
ranges, sensor mounting configurations and wire lengths.
O
ther
manufactures also offer R - T style temperature sensors. However,
these sensors can have very different temperature resistance scales.
Therefore, the
Model 610 Digital Current Monitor is de
signed
to work with the Omega 10K
linear R - T
thermistor
temperature
sensor family, as well as other sensor manufacture's
extre
mely fast
(steep slope) R - T style temperature sensors.
The Model 610's Exhaust and Oil temperature sensor menu
options include the
Omega10K
, and steep slope
PTC
and
NTC
type R - T
thermistor
sensors. The
PTC
(
Positive Temperature
Coefficient) or
NTC
(
Negative Temperature
Coefficient) options
are selected when a steep slope R - T temperature sensor is used.
When t
he
Omega10K
sensor option is selected, the installer sets
Omega10K sensor option is selected, the installer sets Omega10K
the trip temperature in
°
F.
When either the
PTC
or
NTC
sensor
options are selected, the installer enters the trip temperature as the
steep slope sensor's trip resistance in ohms. For example:
If a PTC steep slope, R - T temperature sensor with a trip
resistance of 15K, at the desired trip temperature is used, the
installer would select the
PTC
sensor option, press the
ENTER
button and then use the
UP
and / or
DOWN
buttons to select
15000
ohms
.
Refer to
the
Sequence of Operation
section, paragraph numbers
8 thru 31 (pages 17 & 18) for the
Omega10K
,
PTC
and
NTC
operating details
.
1
.
Select a temperature sensor mounting configuration that
provides a safe and reliable temperature signal for the applica-
tion.
Always select a temperature sensor that exceeds the highest
expected compressor discharge temperature. When available, select
a wire length longer than required for the application.
2.
If additional wire is needed, use 22AWG (minimum) shielded
stranded, twisted pair cable properly insulated for the application.
The maximum length of additional
22AWG
wire is 75 feet. For
longer distances, consult the factory.
3
.
Follow the exhaust temperature sensor manufacturer's instruc-
tions and recommendations when installing the exhaust sensor on
the compressor's discharge line.
4
.
After securely mounting the sensor, refer to
Figure 7,
Model
610 Exhaust Sensor, Oil Sensor and Modbus Wiring Diagram
,
Continued on page 15
Exhaust Temperature Sensor
Installation
Compressor Temperature
Sensing Information
NOTE:
A current above the trip point will not immedi-
ately cause
the
controller to trip. Only when the
integrated excess power, over time, has exceeded
the equivalent to a locked rotor for 2 seconds will
the trip occur. If the over current drops below the
trip value, during the excess power
calculation
,
the controller resets the
excess power
calculator
to
calculator to calculator
zero, thus avoiding nuisance trips. If a different
trip integration time is desired, consult the
factory.
During Temperature Monitoring