Status Instruments DM3600A, Руководство пользователя

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TYPE
This allows the type of input on the unit to be selected. The DM3600 accepts a Voltage, RTD, Thermocouple
or Current Input.
RANGE
Depending on the input type selected the DM3600 will either show the voltage ranges or current ranges
available. Select the range which is applicable to the input device.
LINEARISATION TYPE
The input type selected will determine the linearisation options available. Current/Voltage, RTD or
Thermocouple.
USER LINEARISATION
When the user selects user-linearisation, up to 60 co-ordinate pairs of interpolation data can be entered
via the front panel keys. The ‘
SE9ntS ’ value defines the number of segments.
= Number of interpolated segments = Number of co-ordinate pairs -1
= Electrical input co-ordinate 1
= Process variable (PV) co-ordinate 1
= Electrical input co-ordinate 2
= PV co-ordinate 2
etc......
For n segments there are n + 1 co-ordinate pairs.
If the electrical input goes below electrical input co-ordinate 1, or above electrical input co-ordinate
(n+1), the input is flagged as being under or over-range, respectively.
TEMPERATURE UNITS
This is only available if a Thermocouple or RTD input is selected.
DECIMAL PLACES
The number of decimal places shown on the display can be selected using this option.
DISPLAY VARIABLE
This sets the main display shown by the DM3600 in the run mode. It can be set to show the rate, total or
alternate between both.
INPUT SCALING FUNCTIONALLY
The primary function of a DM3600 is to take an electrical input, and convert it to a displayable Process
Variable (PV, also referred to as an engineering value, e.g. temperature or flow). The DM3600 input signal
can be scaled in one of many ways. For ‘
rtd
’ or ‘
tC
’ inputs, the user is simply required to choose the
‘ tyPE ’ and ‘ Lin ’ (linearity type). For ‘ CurEnt ’ or ‘ uOLt ’ input types, the user can choose STndrd or
AUtO scaling (from the ‘ ScALE ’ sub-menu).
12.1 INPUT MENU BLOCKS
SE9ntS
In1
OUt1
In2
OUt2
ENGINEERING LOW / HIGH
If ‘ Stndrd ’ scaling is chosen, the user will encounter ‘ En9 LO ’ and ‘ En9 HI ’ entries, in order to manually
scale the input to the relevant input_lo and input_hi values (see table overleaf for input_lo/hi values). The
PV_lo & PV_hi values shown overleaf equate to the ‘
En9 LO
’ and ‘
En9 Hi
’ entries). Scaling is subsequently
applied according to the graph overleaf. (The straight line illustrated overleaf will change if a non-linear
linearity type is selected. If the user requires strict control over out-of-range limits, user linearisation
should be chosen).
APPLY AUTO SCALE
If ‘ AUtO ’ scaling is selected, the ‘ APPLy ’ sub-menu appears (in place of ‘ En9 LO ’ and ‘ En9 HI ’ entries).
The ‘
APPLy
’ sub-menu procedure must be carried out as follows.
1. Shift into ‘
APPLy
’ sub-menu.
2. Edit & Enter the ‘ LO uAL ’ engineering value required for low scaling (This will equate to PV_lo).
3. The display will flash ‘ APL LO ’ to prompt the user to apply the electrical signal corresponding to
PV_lo. If the electrical signal goes out of range, the display signifies this, and the input signal won't
be accepted by the DM3600. This applied electrical signal equates to input_lo, in the graph/table below.
4. Repeat Steps 2 & 3 for ‘ HI uAL ’, and the corresponding high electrical/engineering values.
Electrical under
range
limit_lo input_lo input_hi
1.25 % of
(input_hi-input_lo)
7% of
(input_hi-input_lo)
Electrical input
(mV, V, mA)
PV_lo
PV_hi
PV (e.g. level)
Electrical over
range
INPUT TYPE RANGE limit_lo input_lo input_hi
VOLTAGE ± 100 mV -100 mV 0 mV 100 mV
± 10V -10 V 0 V 10 V
± 1V -1 V 0 V 1 V
± 5V -5 V 0 V 5 V
(1 to 5) V 1 V 1 V 5 V
CURRENT (4 to 20) mA 4 mA 4 mA 20 mA
± 20 mA -20 mA 0 mA 20 mA
± 10 mA -10 mA 0 mA 10 mA
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