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1 6 C h a n n e l P T 1 0 0 /C u r re n tM u l t i p l ex e r R T M - 8

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 U X 

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U LTIPLEX

ER S

L E E - D I C K E N S L T DD e s b o ro u g h , K e t t e r in g , N o r t h a n t s N N 1 4 2 Q W U .K .

T e l : (0 1 5 3 6 ) 7 6 0 1 5 6 F a x ( 0 1 5 3 6 ) 7 6 2 5 5 2

Function: The RTM -8 is a 16 channel multiplexer w ith 8 channels for 3 w ire PT100sensors and 8 c hannels for tw o or four w ire transmitter current inputs giving onecurrent output. Each of the PT100 input channels is a complete signal conditionerw ith a DIP sw itch array for coarse setting, and, Span and Zero multi-turnpotentiomet ers for fine tuning on each channel. The RTM -8 is designed formult iplexing a number of analogue signals into PLCs and processor based datagathering devic es. Channel selection is cont rolled by a four line address bus and anEnable line. The RTM -8 is an all solid state inst rument and transfer tim e for theselected channel takes less than 20 microseconds.As noted above, the RTM -8 has an ENABLE control line. W hen disabled the output isin a High Z state allow ing several RTM -8 units to be c onnected in parallel to the same

controller input. The units outputs w ould be tied together and addressed using the sam e address bus but w ith separate ENABLE linesonly one of w hich w ould be enabled at any one time. The period when t he unit is disabled is used for self-testing, according to a self-test procedure w hich checks the unit’s hardw are.

IN PUT S:

RTDs

8 channels of 3 w ire PT100 toBS1904

Temperature RangeZero: –50 to + 200ºCSpan: + 50 to + 750ºC

Current Excitati onLess than 1.1mA

Lead Compensati onError of ± 0.025ºC / 10 ohmslead resistance

Lead ResistanceM aximum 60 ohms (one way)

DC Current8 channels of two w ire orfour w ire transmitters0 to 20mA or 4 to 20mAM aximum input current: 30mAReverse polarity protec ted

Input ImpedanceAddition to loop resistance:350 ohms maximum

O U T P U T :

DC Current

Selected 0 to 20mA or 4 to 20mASettling TimeLess than 20 microseconds(resistive load)

SelectionLogic: 4 Address, 1 Enable/TestLogic Type: True High or TrueLow (user selectable)Logic Levels:

”Low“ < 0.4V” High“ > 5V < 40V

Logic Input ImpedanceGreater than 4K ohm s

SUPPLY:

Power Supply Voltage

24 Volts DC ± 10% (regulated)

Current ConsumptionLess than 100mA in operation

Transmitter CurrentLimited to 40mA ± 2mA

Current LeakageUnmeasurable when disabled

Fuses5 x 20mm quick blowM ain Fuse: 150mA

Pilot LightYellow LED show s Pow er ON

Red LED per active current inputchannel

GEN ERAL :

Accuracy (including Linearity

Hysteresis and Repeatability)PT100: < ± 0.1% of span maxCurrent: < ± 0.1% of span max

Temperature Coefficient< ± 0.1% of span/ 10ºC

Operati ng Temperature Range0 to + 60ºC

Storage Temperature Range –25 t o + 85º C

Operating /Storage HumidityRange5 to 95% RH non-condensing

HousingDIN Rail mounting plastic,polycarbonate

Protection LevelHousing: IP50 DIN40050Terminals: IP20 DIN40050

Weight850 gms

SPECIF ICA T ION S

O RD ERIN G D ETA ILS(a) Give identif icat ion code, i.e. RTM-8(b) Specify temperature ranges for each of the PT100 channels being used, i.e. Channel 1:

0 to 200ºC, Channel 2: 0 to 150ºC, etc.

O 1 2 3

ADDRESS

EO13

O14

O15

O16

9O

10O

11O

12O

4-20mA INPUTS

4-20mA INPUTS

RTD MULTIPLEXER RTM-8

ANALOG +

PLC

ANALOG

INPUT

MODULE

DESCRETE

OUTPUT

MODULE

POWER

SUPPLY

22– 26VDC

ANALOG –

ENABLE

MSB

LSB

+

–

+

–

z s5 z s6 z s7 z s8

z s z s21 z s3 z s4

Pt-100

Pt-100

4-Wire

 TransmitterEXT.SUPPLY

2-Wire

 Transmitter

+  – –

+

D U T+ I –

C D MP WR–  O +

M EC H A N ICA L D ETA ILS

For Mechanical Details see page 7.6.

TERM IN AT ION D ETA ILS