Status Instruments DM3600U, Manual

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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.
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).
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).
12.1 INPUT MENU BLOCKS
SE9ntS
In1
OUt1
In2
OUt2
APPLY AUTO SCALE
If ‘ AUtO ’ scaling is selected, the ‘ APPLy ’ submenu appears (in place of ‘ En9 LO ’ and ‘ En9 HI ’ entries). The
‘ APPLy ’ submenu procedure must be carried out as follows.
1. Shift into ‘ APPLy ’ submenu.
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 and table below.
4. Repeat Steps 2 & 3 for ‘
HI uAL
’, and the corresponding high electrical/engineering values.
OUT OF RANGE ALARM
When an input goes out of range, the following occurs:
If fitted, any relays go into alarm state
If fitted, the re-transmission current derived from the out of range alarm input goes to 3.8 mA or
21.12 mA, depending on whether the burnout setting is set to low or high, respectively.
Once scaling is complete, and the menu structure is exited, if the electrical input is under/over range,
the display shows or
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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