GW Instek GDM-SC1A User manual

Scanner Card
GDM-SC1A
INSTALLATION GUIDE
REV. 01
ISO-9001 CERTIFIED MANUFACTURER

This manual contains proprietary information, which is protected by
copyrights. All rights are reserved. No part of this manual may be
photocopied, reproduced or translated to another language without
prior written consent of Good Will company.
The information in this manual was correct at the time of printing.
However, Good Will continues to improve products and reserves
the right to change specifications, equipment, and maintenance
procedures at any time without notice.
Good Will Instrument Co., Ltd.
No. 7-1, Jhongsing Rd., Tucheng Dist., New Taipei City, 236, Taiwan.

SCANNER CARD
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SCANNER CARD
The optional scanner, GDM-SC1A, lets you
effectively measure multiple channels when
connected to a GDM-8255A, GDM-8261 or
GDM-8261A multimeter. Up to two GDM-SC1A
scanner cards can be installed into the GDM-8255A
or one GDM-SC1A into the GDM-8261 or
GDM-8261A. If two scanner cards are installed,
one can be selected as the master scanner, and the
other as the slave.
Scanner
Installation
Scanner Installation ................................................ 4
Select Channel group and enable scanner ............... 6
Connect wire.......................................................... 10
Scanner Configuration Record ............................... 14
Specification
Specifications ........................................................ 16
GDM-8255A Reading rates &Specifications........... 17
GDM-8261A Reading rates &Specifications........... 17
How to
Thermocouple
measurement
Thermocouple measurement ................................. 23
DMM_SCAN_CARD Software ................................ 26

GDM-SC1A Scanner Card
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GDM-SC1A Basic Specifications
2-wire channel
16 pairs
Maximum current
2A (ch17, ch18)
4-wire channel
8 pairs
Resistance
2/4 wire
Single wire channel
N/A
Cold junction
Temperature
Sensors (Analog)
Maximum voltage
250V
Connection
Screw terminal
Scanner Installation
Configure scanner
Open
Scanner
cover
1. Take off four screws from the bottom panel of the
scanner.
2. Remove the top panel.

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3. Note the connection terminals.
Overview
16 general purpose channels are available, 8 on the left row,
8 on the right row. Current (ACI, DCI) measurement uses
2 extra channels. All channels are fully isolated (Hi and Lo).
Scan/Step
connection
Refer to the below table for measurement and test line
connection. Note: Not all items can be used with GDM-8255A.
Item
No. of wires
No. of channels
DCV, ACV
Diode/Continuity
Period/Frequency
2 wires (H, L)
16 (CH1 ~ 16)
DCI, ACI
2 wires (H, L)
2 (CH17, 18)
Maximum current : 2A
Temperature
simulation
Cold junction
(Separate Chapter)
2 wires (H, L)
2 wires (H, L)
16 (CH1 ~ 16) for
temperature
15(CH2~ 16) for
temperature, CH1 for
Cold junction
2W Resistance
Temp. 2W RTD
2 wires (H, L)
16 (CH1 ~ 16)
4W Resistance
Temp. 4W RTD
4 wires
(Input H, L
+ Sense H, L)
8 pairs (CH1 [input]&
9[sense], 2&10,....8&16)

GDM-SC1A Scanner Card
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Select Channel group and enable scanner
Background
When 2 scanner modules are installed in the
GDM-8255A, 2 groups of 18 channels each are
available. The scanner modules have a jumper to
configure which scanner is for which group. If only
one scanner is installed, the scanner should always
be configured to group 1(CH101~CH118).
The GDM-8255A can have up to 2 scanner modules
installed, whilst the GDM-8261/GDM-8261A can
have only 1 scanner module installed.
Group1
CH101 ~ 118
Group2
CH201 ~ 218
Select group
(Jumper J8)
(Preset
MASTER)
Set the jumper J8 in the center of the board
accordingly. Move the jumper to the right for
selecting CH1xx (101 ~ 118), and move to the left
for selecting CH2xx (201 ~ 218). If two scanners
are installed, set one scanner to Master (CH1xx) and
the other to Slave. If only one scanner is installed,
set the jumper to Master.
CH201-218
SLAVE
CH101-118
MASTER
J8
SS

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Enable scanner
(Jumper J9)
(Preset Enabled)
Set the jumper J9 on the rear side of the board
accordingly. Move the jumper up to disable the
scanner, and down to enable the scanner.
Enable cold
junction points
(Jumper J10)
(Preset Disabled)
Set the jumper J10 on the Bottom left of the
board accordingly. Move the jumper up (COLD
COMPEN) for selecting CH1 to Enable the Cold
Junction, or down(CH1) for selecting CH1 to
Disabled the Cold Junction.
J10
COLD
COMPEN
CH1
J9
Disable
Enable

GDM-SC1A Scanner Card
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Note
Do Not set the jumpers horizontally as the figure
below shown, which will Not enable the target
functions.
Erroneous
example

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Temperature sensor Calculation
Overview
The temperature sensor provides a positive slope
output of 10 mV / °C
Equation
The temperature sensor voltage output (Vout)
calculates given temperature (Ta):
Ta = (Vout –Voffs) / Tc (Equation)
where
• Vout is the temperature sensor voltage output for a
given temperature
• Ta is the given temperature °C
• Tc is the temperature coefficient 10mV/ °C
• Voffs is the temperature sensor voltage offset =
500mV
Example
The temperature sensor voltage 0.785V
Ta = (0.785 –0.5 ) / 0.01 = 28.5°C
The calculates given temperature 28.5°C

GDM-SC1A Scanner Card
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Connect wire
Wire selection
Make sure the wires have at least the same Voltage and
Current capacity as the maximum ratings in the
measurement.
When measuring TC, it has the possibility that CH1 is
being regarded as cold junction. In order to prevent
conflicts, it is suggested initiating from CH2 for wiring.
Connection
1. Turn the screw left (loose) using the screw driver
and insert the wire. Turn the screw right (tight) and
secure the connection.
Tighten
Loosen Insert
2. Route the wires as follows, using the two openings
(left and right) at the front cover.

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Note
When using thermocouple measurement, The
temperature sensor inside the scanner box. Move
the J10 JUMP to cold compensation, and the CH1
value is switched to the temperature sensor value.
You can use this temperature as a cold junction
compensation.
Temperature Sensor
J10 CH1
When J10 JUMP is set to cold compensation,
CH1 original connection external signal will lose
its function, Change to the temperature sensor
3. Tightly bundle the wires with cable ties which go
through the bottom holes at the front cover as the
following figures shown.

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4. Close the top cover and tighten the screws from the
bottom.
Configuration
Record
Print out the configuration record list on page14, fill in
the details, and keep it with the DMM.
Insert scanner
Power Off
Turn the Power Off and take out the power cord.
Open the rear
panel slot
Take out the two screws on the slot corners to
remove the optional slot cover. Keep the screws for
later reuse.
GDM-8255A shown

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Insert the
scanner
Insert the scanner (already configured according to
the procedures on page4) to either the top or
bottom slot (GDM-8261/GDM-8261A only has 1
slot). Close the cover by tightening the screws.
GDM-8255A shown
Power On
Connect the power cord and turn On the power.
CAUTION
Do not input voltages exceeding 250V to the front
input terminals whilst the scanner module is
installed.
WARNING
Do not connect any leads to the front input
terminals while the scanner is active. Input signals
scanned by the scan module also appear on the
front terminals.

GDM-SC1A Scanner Card
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Scanner Configuration Record
Channel
Wire color
Measure type
Note
CH1
H
L
CH2
H
L
CH3
H
L
CH4
H
L
CH5
H
L
CH6
H
L
CH7
H
L
CH8
H
L
CH9
H
L
CH10
H
L
CH11
H
L
CH12
H
L
CH13
H
L
CH14
H
L
CH15
H
L
CH16
H
L
CH17
H
L
CH18
H
L
CARD INPUT
H
L
CARD SENSE
H
L
AMPS
H
L

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Specifications
General
Note
All specifications are ensured only under a single
display.
At least 30 minutes of warm-up time is required
before applying these specifications.
General
measurement
channels
16 channels of 2-pole relay input, which are configurable
to be 8 channels of 4-pole inputs
Dedicated
current
measurement
channels
2 (Channel 17,18)
Maximum Signal
Level
Channels 1-16: 250V DC or rms, 1A switched, 30 W,
62.5VA (resistive load)
Channels 17-18: 60V DC or 30V rms, 2A switched, 30 W,
62.5VA (resistive load)
Resistance
Measurement
2/4 Wire
Cold Junction
Compensation
Temperature Sensor Tmp235
Contact
Resistance
<1Ωat the end of contact life
Contact Life
>105operations of rated load (resistive loads only)
>108operations of cold switching
Relay Actuation
Time
<6ms
Isolation
between any two
channels
>1010Ω,<100pF
Input
Differential
Isolation
>1010Ω,<75pF
Connection
Screw Terminal
Operation
Environment
Ambient Temperature 0°C~40°C, Relative
Humidity<75%
(For full accuracy: 18°C ~28°C)
Temperature
Coefficient
<0.2 x applicable accuracy per degree (°C)
(for 0°C ~18°C and 28°C ~40°C)
Storage
Ambient Temperature -10°C ~70°C

GDM-SC1A Scanner Card
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Environment
Relative Humidity: 0°C ~35°C <75%, 35°C ~50°C <50%
Dimension
121(W) x 22(H) x 178(D) mm
Weight
260 grams
GDM-8255A Reading rates (readings/sec)
Note
Test conditions: Auto mode off, auto range off, in
simple mode with default delays.
The test items listed below may require proper delay
to obtain in-spec reading.
Function
Rate(readings/sec)
S
M
F
DCV
5
7.5
11
DCI
5
7.5
11
ACV
0.3
0.4
0.4
ACI
0.3
0.4
0.4
2/4WΩ
(10M/100MΩ)
1.1
1.7
2.3
ACV+DCV
1.2
1.8
3.5
ACI+DCI
0.3
0.5
0.6
Diode
7.9
7.9
13
GDM-8261/GDM-8261A Reading rates (readings/sec)
Note
Test conditions: Auto Range Off, Auto Zero/Gain
Off, ADC Speed: Quick, Count: 10, All Delays are set
to zero.
The test items listed below may still need proper
delay to obtain in-spec reading.
Function
Rate(readings/sec)
S
M
F
Comments
DCV
4.35
16.4
29
ACV
0.3125
0.53
0.7
AC BW=3~300kHz
DCI
2.5
5
10
ACI
0.32
0.53
0.625
AC BW=3~300kHz
2/4 WR
4.31
16.4
30.5
Diode/Cont
11.23
18.5
23.35

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GDM-8255A Reading rates-Frequency (readings/sec)
Note
The signal being measured must be:
≥ 0.1V rms when its frequency is lower than
100kHz
≥1V rms when its frequency is lower than 600kHz
≥2.5V rms when its frequency is lower than
800kHz
Bandwidth of frequency measurement: 10Hz ~
800kHz
* Signal frequencies lower than 150Hz may need
proper delay to obtain in-spec reading.
Frequency
Rate(reading/sec)
Under 150Hz
1.1*
150Hz ~ 1.5kHz
1.8
1.5kHz ~ 15kHz
2.6
15kHz ~ 150kHz
4.5
Above 150kHz
12
GDM-8261 Reading rates-Frequency
(seconds/reading)
Note
Test Conditions: Auto Range Off, Filter Off, Auto
Zero/Gain Off, Count: 10, All Delays are set to zero,
D-Shift: On
Bandwidth of Frequency Measurement:
3Hz~300kHz
Speed
Signal Level
Rate (Second/Reading)
Slow
100mV rms
2.62 Sec@3Hz
2.18 Sec@300kHz
Mid
100mV rms
552 mSec@20Hz
500 mS @300kHz
Fast
100mV rms
236 mSec@200Hz
200 mS @300kHz
GDM-8261A Reading rates-Frequency
(seconds/reading)
Note
Test Conditions: Auto Range Off, Filter Off, Auto
Zero/Gain Off, Count: 10, All Delays are set to zero,
D-Shift: On
Bandwidth of Frequency Measurement:
3Hz~300kHz
Speed
Signal Level
Rate (Second/Reading)
Slow
100mV rms
2 Sec@3Hz
1.8 Sec@300kHz
Mid
100mV rms
552 mSec@20Hz
548 mS @300kHz
Fast
100mV rms
332 mSec@200Hz
332 mS @300kHz

GDM-SC1A Scanner Card
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DC Voltage
Note
*: 250V is the maximum input voltage limitation of
GDM-SC1A Scanner card though it is in fact used in
the 1000.00V range.
Maximum Input: 250V DC or Peak on all ranges
Rate
Range
Accuracy
±(% of reading + digits)
Slow
100mV
0.015%+10
1V
0.015%+7
10V
0.015%+7
100V
0.015%+7
250V*
0.015%+7
2W Resistance
Note
Maximum Input: 250V DC or 250Vrms AC
*: Ranges on which residual resistance needs to be
manually offset from readings when measuring.
Rate
Range
Accuracy
±(% of reading + digits)
Slow
100Ω
0.125%+10*
1kΩ
0.1%+7*
10kΩ
0.075%+7*
1000kΩ
0.075%+7
1MΩ
0.075%+7
10MΩ
0.375%+7
100MΩ
3.75%+10
4W Resistance
Note
Maximum Input: 250V DC or 250Vrms AC
*: Ranges on which residual resistance needs to be
manually offset from readings when measuring.
Rate
Range
Accuracy
±(% of reading + digits)
Slow
100Ω
0.0625%+10*
1kΩ
0.0625%+7*
10kΩ
0.0625%+7*
100kΩ
0.0625%+7
1MΩ
0.0625%+7
10 MΩ
0.375%+7
100MΩ
3.75%+10

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DC Current
Note
Maximum Input: : 2A
When GDM-SC1A scanner card is used, 1A & 10A
ranges are protected with a 3A/125V fuse
Current ranges smaller than 1A are not selectable
when GDM-SC1A scanner card is used.
Rate
Range
Accuracy
±(% of reading + digits)
Slow
1 A
0.25%+7
AC Voltage
Note
Maximum Input: AC 250V rms
The specifications are only applicable for sinusoidal
signals with amplitudes greater than 5% of the Full
Scale reading.
(*)Input <200V for 20~45Hz. 250V is the maximum
input voltage limitation of GDM-SC1A Scanner card
even though it is used in the 750.00V range.
Rate
Range
Accuracy (reading%+digits)
Slow
20~45Hz
45~10kHz
10k~30kHz
30k~100kHz
100mV
1.25%+125
0.25%+125
1.875%+375
6.25%+375
1V
1.25%+125
0.25%+125
1.25%+125
3.75%+250
10 V
1.25%+125
0.25%+125
1.25%+125
3.75%+250
100V
1.25%+125
0.25%+125
1.25%+125
3.75%+250
250V(*)
1.25%+125
0.25%+125
1.25%+125
3.75%+250
AC Current
Note
Maximum Input: : 2A
The following specifications are only applicable for
sinusoidal signals with amplitude greater than 5% of the
Full Scale reading
1A & 10A ranges protected with a 3A/125V fuse
1A/10A range specifications are verified for < 5kHz
Rate
Range
20~50Hz
50Hz~ 10kHz
10kHz~ 20kHz
S
1A
--
1.25%+125
--

GDM-SC1A Scanner Card
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AC Frequency
Note
Maximum Input: 250Vrms or 330V peak.
Rate
Sensitivity
10Hz~100kHz
100k~600kHz
600k~800kHz
Slow
2.5V
0.0625%+19
0.0625%+4
0.0625%+4
1V
0.0625%+19
0.0625%+4
--
0.1V
0.0625%+19
--
--
Diode/Continuity
Note
Max. Input: 250V DC or 250 V rms AC
Diode
Range
Approx. 2V, (8255A)
Approx. 1.4V, (8261A)
Continuity
1 ~ 1000Ω
Temperature
Note
The associated errors in temperature measurement
include temperature sensor (thermocouple), wire and
error measured by DMM and SCANNER CARD. In
temperature measurement, the largest source of error
is usually the temperature sensor (thermocouple) itself
GDM-8255A Temperature Characteristics
Note
Sensor errors excluded from Temperature
specifications
Type
Measurement Range
Resolution
J, K, T
-200 ~ +300°C
0.01°C