MKII - Units with serial numbers above 112000
PUSH BUTTON PT100 TEMPERATURE TRANSMITTER
Mounting holes:
2 holes 0.22” (5.5mm) diameter, 1.3” (33mm) centers
Center hole sensor wire entry:
0.16” (4.0mm) diameter
Side View
1.69”
(43.0mm)
1.3”
(33.0mm)
Centers
0.83”
(21.0mm)
Base View
Figure 1
1.0 DESCRIPTION
The SEM203P MKII head mounted temperature transmitter connects to any standard pt100 resistance sensor and con-
verts the linearized temperature to a (4 to 20) mA signal. The transmitter is a two wire device, and is fully configurable
by the user, over a wide temperature range, with the aid of a simple push button. This new SEM203P MKII design
incorporates additional configuration menus, allowing the user to push button trim the transmitter output at both zero
and span, ideal for trimming out sensor errors and choose between upscale or downscale burnout (upscale is default).
The transmitters advanced circuitry guaranties high stability over the wide operating ambient temperature ranges
experienced by head mounted devices.
One of the transmitters features is the program LED, which provides visual indication of sensor fault when in normal
operation and is also used to guide the operator through the simple menus during configuration.
2.0 RECEIVING AND UNPACKING
Please inspect the packaging and instrument thoroughly for any signs
of transit damage. If the instrument has been damaged, please notify
your supplier immediately.
3.0 SPECIFICATION @ 68°F
INPUT
Sensor Type
PT100 100
⍀
@ 0°C 2 or 3 Wire
Sensor Range
(-328 to +1562)°F - (18 to 390)
⍀
Sensor Connection
Screw terminal
Minimum Span (see Note 1)
40°F
Linearization
BS EN 60751 (IEC 751) standard /JISC 1604
Accuracy (see Note 2)
± 0.2°F ± 0.1% of Reading
Thermal Drift
0.005% / °F
Excitation Current
<200 uA
Lead Resistance Effect
0.004°F /
⍀
Maximum Lead Resistance
20
⍀
per leg
Note 1 Any span may be selected, full accuracy is only guaranteed
for spans greater than the minimum recommended span.
Note 2
Basic measurement accuracy include the effects of calibration,
linearization and repeatability.
OUTPUT
Type
Two wire (4 to 20) mA sink
Limits
Low 3.8 mA; high 21.5 mA
Accuracy
± (mA out / 2000) or ± 5 uA which
ever is greater
Loop Effect
± 0.2 uA / V measured @ 50 Hz 1 V
(peak to peak)
Thermal Drift
± 0.06 uA / °F typical; ± 1.5 uA Max
Max Load
[(V supply – 10) / 20] K
Ω
GENERAL
Update Time
0.5 Seconds
Response Time
1 Second to reach 90% of final value
Start up time
From power up typically 5 Seconds
Filter Factor
Adaptive
Ambient Temperature
(-40 to 185) °F
Connection
Screw Terminal
Approvals
BS EN 61326; 1998 – Electrical
equipment for measurement and
control ANNEX A; ANNEX F
Factory Default
(0 to 100) °C upscale burnout
(0.0 °C user trim)
4.0 INSTALLATION AND WIRING
4.1 Mechanical
The SEM203P transmitter has been specifically designed to fit inside a DIN standard probe head
enclosure (such as the Status SCH-4 series), which provides adequate protection from moisture,
dust, corrosive atmosphere etc. All cable entries must be sealed using the correct size gland.
Likewise any probe assembly fitted must be sealed. Care must be taken when locating the transmitter
to ensure the working ambient temperature range of (-40 to 185°F) is not exceeded. The SEM203P
enclosure has a center hole allowing the sensor wires to enter screw terminals from the transmitter
center, this is applicable when the sensor is mounted directly below the transmitter.
4.2 Electrical
Electrical connections to the transmitter are made to the screw terminal provided on
the top face. The sensor wires must be equal length and type for the lead compensa-
tion to work correctly. The screw terminals allow for wires to enter either inner or outer
direction. The transmitter is protected against reverse connection and over voltage. If
no sensor (input) connection is made, the transmitter will go into either up or down
scale output current, depending on configuration.
Figure 2 gives connection details, the output is shown connected to a 24 V supply. The
load symbol represents any other device connected in the loop, such as monitoring
equipment, panel indicators and loop isolators. The load value can range from 0 ohms
to the max loop load for given supply, refer to section 3 “Max Load” for more informa-
tion. The transmitter conforms with EC directive BS EN 61326; 1998 when correctly
installed in a termination head providing at least IP20 protection and with sensor wires
less than 3 meters. Shielded or twisted pair wires are recommended for output wires.
Always ensure the (4 to 20 mA) loop is grounded at one point, this would normally be at
the monitoring equipment or loop power supply.
In normal operation the program LED acts as over-range LED.
Figure 2
WHITE
Load
POWER
SUPPLY
Pt 100
RED
RED
OPERATING SPECIFICATIONS
SEM203P MKII
When using a 2-wire RTD put a jumper across terminals connected to red wires in Figure 2.
