EastwoodLab QR10 Pocket Programmable Resistance Box User Manual

QR10 Pocket Programmable Resistance Box

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Specifications

• Product Name: QR10x General-Purpose Pocket Programmable
  Resistance Substitution Box

• Model Number: QR100

• Website: www.eastwood.tech

• Revision: 3.0 | Jun.2023

• COM Port: Available for advanced applications like data
  acquisition and auto-tests

• Features: No residual resistance, wide range of
  applications

Product Usage Instructions

1. Connection: Connect the device to a PC via a
   USB type-C cable.

2. Driver Installation: Install the driver
   manually or let the PC auto-scan for installation.

3. Device Manager: Check Baudrate settings and
   End mark (EOT) in Device Manager (Windows).

4. AT Command Set: Use AT commands for remote
   control and checking device information.

Frequently Asked Questions (FAQ)

Q: What are the basic AT commands for the device?

A: Basic instructions include Get SP, Set SP, AT+USER.SP?,  

AT+USER.SP=, AT+USER.SP+=, AT+USER.SP-=. Make sure to add r’ or n’ at the end of each command.

Q: How can I increase the Set Point (SP) value?

A: Use the command AT+USER.SP+= followed by the desired  

value.

Q: Do I need to reboot the device after changing settings?

A: For FW v5.93~v5.96, you may need to reboot the device after  

saving and paging down to apply new settings.

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QR10x General-Purpose Pocket
Programmable Resistance Substitution Box
Specification & User’s Manual
(Since Kickstarter Campaign Batch)

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Rev. 3.0 | Jun.2023

As a candidate for replacing/upgrading conventional resistance decade box, QR10 has as good as, if not better than, the top class of the latter on the accuracy, range, resolution/step, repeatability, and temperature coefficient. It provides a ” better operation experience ” on the user interface, much higher rated power, and much smaller dimensions. More importantly, it’s just a ” programmable ” resistance substitution box the way it should be ­ the user can either set desired output value by an integrated keypad or remotely control it via a USB-Serial COM port.
The COM port mentioned makes it suitable for advanced applications such as data acquisition and auto-tests, for example, sensor simulation and sensor auto-calibration.
what is more, thanks to the design solution and approach chosen, QR10 can use standard key components to improve quality and reduce cost; And, allowing user calibration makes it easy for maintenance and keeps long-term accuracy as well

Key Features o “True” resistance generated by relayresistor network o Easy-to- use keyboard and useful OLED display o USB to serial communication interface, support private AT instruction set o Initial high accuracy (>500): ±0.05%(class T) ±0.02% (class B)
o NO RESIDUAL RESISTANCE o Wide range:
1 -630k (0.1/0.07 steps) 1 -1.2M (0.125 steps) 1 -8.4M (1 step) o Maximum power rating up to 2.0W o Safety output limit(user definable) o Latched output with ZERO power consumption o Allow user field calibration (after calibration accuracy can follow reference meter’s for grade B) o Rechargeable Li-PO battery o Portable with small dimensions and solid metal housing: 5.5cm (OD)× 5.5cm (H) or 7.0cm (H)
Applications o Traditional resistance boxes replacement o Industrial automation testing o Resistive sensor simulation o Resistive sensor calibration o Online debugging of circuits o ……

0.3%

Typical Accuracy@Tcal±1

0.2%

0.1%

PV Err.

-0.1%
-0.2%
-0.3% 1

PV Err. + Tol.(B class) -Tol.(B class)

10

100

1,000

10,000

100,000

1,000,000

PV()

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Rev. 3.0 | Jun.2023

Abbreviation/terminology checklist

SP PV TC or TCR Tcal T
NPLC
EMF (On OLED)K (On OLED)M MaxU or (On OLED)U< (On OLED) F
(On OLED) U_
(On OLED)R> (On OLED)TS (On OLED)VB (On OLED)STP (On OLED)TOL (On OLED)RGE (On OLED)PWR (On OLED)OTR (On OLED)C/T (On OLED)H/W (On OLED)F/W (On OLED)S/N (On OLED)PRD

Set Point (by user) Process Value, or output value/return value (by the device) Temperature Coefficient of Resistance Calibration Temperature Temperature difference, specifically refers to the difference between the test ambient temperature and the calibration temperature Number of Power Line Cycles Thermal Electromotive Force k M
The highest allowable voltage across the output The factory calibration data is activated
The user calibration data is activated
Minimum output limit value Internal Temperature Sensor Voltage of Battery Step Tolerance Output Range Rated Power Operating Temperature Range Calibration Temperature Hardware version Firmware version Serial Number Date of Production

Order code 1,2,3

QR100

–

A : ±0.01%, TC<25 ppm

B : ±0.02%, TC <25 ppm

Valid Order

T : ±0.05%, TC <50 ppm

code

QR101

–

A : ±0.01%, TC <25 ppm

B : ±0.02%, TC <25 ppm

T : ±0.05%, TC<50 ppm

– 1K-R1 2K-RX AK-1R
– 1M-R1 2M-RX
AM-1R5

: 1 ~870, 0.1 /0.07 steps4 : 1 ~1.7k, 0.1 25 steps : 1 ~11.5k, 1 steps
: 1 ~630k, 0.1 /0.07 steps 4 : 1 ~1.2M, 0.125 steps : 1 ~8.4M, 1 steps

1 For detailed definitions such as accuracy, please refer to the specification below.
2 Accurate output ranges vary from machine to machine and batch to batch. In general, the difference in the
maximum output is within 5% of the given value in the above table, and the minimum output value is about 1.0 . 3 Class A production is suspended. Users can self-calibrate Class B or T using a high-grade reference meter to
achieve higher accuracy. 4 For 0.1 stepping models, subsequent manufacturing will upgrade to 0.07 steps. 5 Production of QR101B-AM-1R is suspended and QR101T-AM-1R is available.

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Rev. 3.0 | Jun.2023

Specification (The yellow highlighted sections are the main additions or modifications to the datasheet)

Key parameters

QR100/101

Remark

Output

Initial accuracy

Class
Range < 500 500 ~ 2 M >2 M

T @Tcal±5 °C
±0.25 ±0.05% ±0.1 %

B @Tcal±3 °C
±0.1 ±0.02% ±0.05 %

1. Under no load, operation <1 × 10^6 times
2. Calculated by PV

Nominal stepping Difference between SP and PV Overall TC >100 Rated power
Short-cut and open-circuit Relay type Relay reliability
Minimum contact rating for relays / Minimum load for the output
Relay group switching time
Relay group switching mode Recommended max operating frequency Max operating frequency
Output terminals Communication interface Power supply (and for recharging) Max peak current Power supply connector

0.1 /0.070.125 or 1.0 < 1 nominal step, the typical value is 0.3 nominal step Class T: <50 ppm Class B: <25 ppm 1.0~2.0 W (up to 200 Vdc), depending on the output resistance Not supported Bistable signal relays (electromagnetic relays) Underrated load*: > 1 × 10^5 times No load: > 1 × 10^7 times 10uA @ 10 mVDC
QR100< 55 ms QR101< 95 ms In natural mode, the output may be open or short- circuited during the switching 1Hz 5Hz
Terminal posts, 2-wire
5V±0.25V, 100mA min. About 50mA@5V< 0.1s Via USB type-C

Please refer to the COM port return data
*Rated load of relay: 1A@30 VDC or 0.3A@125 VAC This value may vary depending on the frequency of operation and the usage environment. Use below this value may cause malfunction
Under the condition of small power applied to the output
Happens only when relays are switching

Communication bus

USB to serial port (COM)

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Rev. 3.0 | Jun.2023

Specification(continued)

Driver IC Baud rate & settings Protocol Other features Keypad
Display Display resolution

WCH CH340 115,200 bps, 8 data bits, no parity, and 1 stop bit Private AT command set (see below)

Mechanical keys with silicone rubber caps
0.54” OLED, monochrome SP: 0.1 or 6 digits PV: 1 m or 6 digits

non-waterproof

Internal temperature measurement User field calibration
Scanning output Safety output limit Power saving
Others Battery type Battery life Battery charging time

Yes, the typical accuracy is ±0.1

Yes. Guarantee that the output accuracy after calibration is not lower than the initial accuracy; Guarantee that for B/A class the output accuracy can theoretically follow the reference table accuracy (±0.003% of the reading ±10m) in a short period after calibration*
Yes
Yes, user-defined
Turn off display after 1 min of inactivity; Shut down after 1 h of inactivity if without USB cable connected

• The actual results are related to the reference meter’s accuracy/ linearity, the correctness of calibration operations, and device hardware stability.
  Refer to keypad operation

Rechargeable Li-polymer. 500+ charge/discharge cycles
About 12h@ 1Hz operation 3 hours

Battery Shelf life Operating temperature

10 month. Re-charge the battery every 8 months is recommended -10 °C ~ 40 °C

Relative humidity
Storage temperature Housing material

10 % to 95 % non-condensing
-20 °C to 75 °C Brass (cup), Dioxide aluminum alloy (lid)

Dimensions Weight Accessories Warranty

QR100: 5.5 cm (OD) × 5.5 cm (H) QR101: 5.5 cm (OD) × 7.0 cm (H)
QR100: about 215g QR101: about 252g
M4 banana plug cable* ×2 Class B provides a factory calibration certificate (electronic version, see Appendix 1) 1 year

*25m per single Indoor use only

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Rev. 3.0 | Jun.2023

Typical characteristics
Unless otherwise noted, all tests are based on test data of Class B samples at room temperature, and the accuracy in the table is the relative accuracy based on the reading of the reference meter. The uncertainty of the reference meter used is better than ±0.013% in the <1M range. The uncertainty of the reference meter should be considered when deriving the absolute accuracy.
Definition: T = ambient temperature at test ­ Tcal

0.04%

Typical Output Repeatability@T=±0.2

0.03%

0.02%

0.01%

0.00%

-0.01%

-0.02%

First round

-0.03%
-0.04% 1

Class B tolerance

10

100

1,000

10,000

100,000

1,000,000

Above: Repeatability is based on the results of 8 consecutive rounds of testing of the same sample at room temperature (fluctuation range of about ±0.2°C). Errors are based on comparison with the results of the first round.

0.05%

Typical Output Accuracy@T=±3

0.04%

0.03%

0.02%

0.01%

0.00%

-0.01%

-0.02%

-0.03% 10

100

1,000

10,000

100,000

1,000,000

Above: Accuracy is based on 10 consecutive rounds of testing of the same sample in a thermostat (temperature variation range: Tcal-3°C to Tcal+3°C). Errors are based on direct comparisons with reference meter readings and do not include the uncertainty of the reference meter itself.

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Rev. 3.0 | Jun.2023

Output() 0.00 0.02 0.02 0.04 0.04 0.05 0.05 0.06 0.07 0.09 0.11 0.12 0.14 0.14 0.16 0.17 0.19 0.21 0.23 0.24 0.25 0.26 0.28 0.30 0.32 0.33 0.33

Typical characteristics (continued)
Typical relay group switching time (30ms)
5,800 5,300 4,800 4,300 3,800 3,300 2,800
Time(s) Above: Typical relay group switching time. The example is monitoring the process of switching from 3k to 4k, with the measurement mode 2-wire and the configuration NPLC=0.05.

Output()

8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000
0 0

Typical relay group switching noise Switching noise

1

2

3

4

5

6

7

Time(s)

Switching noise

8

9

Above: The “output resistance noise” generated by relay switching occurs on the rising or falling edge, and is more obvious during some resistance switching. It should be noted that the relay switching algorithm of the QR10 is not specifically optimized, so in some cases, the output may be open or shorted for a short period (ms level).

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Rev. 3.0 | Jun.2023

66

63

36 39 42 45 48 51 54 57 60

Typical characteristics (continued)

0.9509 0.9508 0.9507 0.9506 0.9505 0.9504 0.9503

0 3 6 9 12 15 18 21

24

Typical output drift(1) Time(s)

99.9640 99.9635 99.9630 99.9625 99.9620 99.9615 99.9610 99.9605

Typical output drift(100)

24

0 3 6 9 12 15 18 21

Time(s)

Typical output drift(10k)

9,999.980 9,999.975 9,999.970 9,999.965 9,999.960 9,999.955 9,999.950 9,999.945 9,999.940

0 3 6 9 12 15 18 21

24

Time(s)

27 30 33 36 39 42 45 48 51 54 57 60

27 30 33 36 39 42 45 48 51 54 57

27 30 33 36 39 42 45 48 51 54

63

60

57

66

63

9.97230 9.97225 9.97220 9.97215 9.97210 9.97205 9.97200 9.97195 9.97190 9.97185

0

3 6 9 12 15 18 21 24 27 30

Typical output drift(10) Time(s)

33

Typical output drift(1k)

1,000.0250 1,000.0245 1,000.0240 1,000.0235 1,000.0230 1,000.0225 1,000.0220 1,000.0215

0 3 6 9 12 15 18 21 24 27

30

Time(s)

Typical output drift(100k) 100,001.2 100,001.1 100,001.0 100,000.9 100,000.8 100,000.7 100,000.6 100,000.5
Time(s)

32

0 3 6 9 12 14 17 20 23 26 29

66

63

33 36 39 42 45 48 51 54 57 60

63

35 37 40 43 46 49 52 55 58 60

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Rev. 3.0 | Jun.2023

Rated voltage(V) 0 3 6 9
12 14 17 20 23 26 29 32 35 37 40 43 46 49 52 55 58 60 63

Typical characteristics (continued)

1,000,014 1,000,012 1,000,010 1,000,008 1,000,006 1,000,004 1,000,002 1,000,000
999,998 999,996

Typical output drift(1M) Time(s)

Above graphs: Due to factors such as relay EMF, parasitic capacitance/inductance, the measuring instrument itself, or the measurement method, it usually takes some time for the output resistance measurement to stabilize (excluding relay contact oscillations), the process can last for seconds or even minutes (experience shows that it is related to the number of relays involved in switching). This phenomenon should be considered in high- precision or high-frequency switching applications. The test is performed by starting the measurement at the first moment of the new value output (t=0) and recording the measurement data for about 1 min (the above measurement is performed using a 4-wire system with NPLC=5 and a switching sequence of 1M-1-10-100-1k -10k -100k -1M).

Actual maximum allowable voltage (typical) 200

Maximum voltage (1W calculated)

150

100

50

0

1

10

100

1,000

10,000

100,000 1,000,000 10,000,000

PV()

Above: The power rating of the base resistor is 1W, while in practice for most output values (PV), the power rating is usually between 1W and 2W. The user can use it according to the actual MaxU (rated voltage) returned from the serial port; for simplicity, it can also be always treated as 1W according to the rated voltage calculated by the formula MaxU= (PV*1). It should be noted that the maximum applied voltage
across the output resistor should not exceed 200V.

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Rev. 3.0 | Jun.2023

Principle of operation

Above: QR101 relay-resistor network schematic (while number of QR100 base resistors is 14). The algorithm is to selectively control the opening and closing of the switches/relays (S1~S24) to selectively pass or shield the base resistors (R1~R24), thus outputting the resistance value (PV) that is closest to the set value (SP). The nominal step value is determined by the smallest base resistance value, and the device cannot perform a scanning output with a smaller step.
Interface

USB Type-C port for communication
and recharging

Grounding solder lugs for shielding
and safety

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Output terminal posts
ON/OFF
Rev. 3.0 | Jun.2023

Instructions for use
Communication isolation protection To prevent introducing external interference and to avoid the risk of electric shock during highvoltage use, please use the USB communication isolation module to isolate the host computer and this device.
Electric shock! Since the output resistance of this product supports a maximum voltage of 200V DC/AC, when the output terminal is connected to high voltage (>=36V DC/AC), the equipment must be grounded (as well as the hardware isolation of the communication port), and it is forbidden to touch the output terminal to avoid harm or damage to personnel or equipment.
Operating temperature and humidity Please use it within the recommended operating environment. Excessive temperature may cause abnormal operation or damage to this device as well as cause a reduction in the rated power of the output resistance; high humidity or condensation may affect the accuracy of the output resistance (especially for above 1M) as well as reduce the service life of the device.
Installation Not properly grounded results in poor shielding and poor electrical leakage protection.
Power supply When used stand-alone, the device uses power from an internal lithium battery. The endurance time is related to the user’s operating frequency, generally for several days or weeks. The device will automatically shut down after one hour of no operation. The system will detect the voltage of the lithium battery at each power-on, and cannot be turned on if it is lower than 3.6V, so it should be charged in time.
The product can be powered by a normal USB Type-C cable (for lithium battery charging and serial communication). In the case of an external power supply, the device will disable auto-shutdown.
Testing It is critical that the test equipment cables are well shielded and properly grounded, otherwise noise interference may be introduced. The recommended wiring is shown in the following diagram:

It should be reminded that the distortion of the power supply waveform and noise may also have an impact on the test results, especially if the test instrument shares power with a high-power inductive load. In addition, two- wire measurement must take into account the influence of the resistance of the probe wire.

User calibration
Having a trusted reference meter, stable ambient temperature, and proper operation (especially for measurements above 1 M) can bring the module to at least the accuracy claimed in the specification after calibration. In the short term, it is guaranteed that products of class B/A can theoretically follow the reference table accuracy after calibration (plus uncertainty: ±0.003% of the reading ±10m).

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Rev. 3.0 | Jun.2023

Keypad operation (since FW v5.93)

Item Function/Display

Operation

Note/Example

1

Boot up (ON)

Press and hold the red key until you see the startup screen

1.1

Display auto turn The screen turns off automatically after 1

off

minute of inactivity.

Press any key to wake up the screen.

USB-Serial COM still working properly under this condition

2

Shutdown (OFF)

Press and hold the red key until the screen

dims or shuts off

2.1

Auto shutdown

Without USB cable power supply, the system will shut down automatically after 1 hour of inactivity of key operation; With USB cable, auto shutdown is disabled.

Page 0 (main page)

3

Page 0 (main

page)

If there is no other operation after booting, the screen that displays “U</SP/PV” is page 0.

By default, row SP is hidden (except SP unit).

3.1

Set SP

To show SP, hold for 1.5 sec. On page 0

Note: The first digit of the set

Number key 0~9 / the black key (decimal

value cannot be a decimal point.

point) + the red key (enter/ok)

3.2

Cancel SP setting During 3.1 editing (before clicking the red key): The system will return to page 0

– double click to cancel editing.

3.3

Change SP unit

– Two decimal points in the SP string like “123.45.” will also cancel editing.
On page 0

Click , SP unit changes in the order of “” “K(k)” “M(M)”

3.4

Rated power

On page 0

After each update of SP, the

The first line “U<” indicates the rated voltage corresponding rated voltage

of the current PV

value is also refreshed.

3.5

Output value (PV) On page 0/2, row 3

The definition of accuracy is

based on PV and its

corresponding reference value.

Page 1 (sensor page)

4

Page 1

On page 0, click to switch to page 1

4.1

Battery voltage

(VB)

4.2

Temperature

Sensor (TS)

4.3

Back to page 0

On page 1 (row 1) On Page 1 (row 2) On page 1, click ,

Cannot boot up if VB<3.6 V. Normal VB ranges from 3.6 V (low power) ~ 4.2 V (fully charged) It might be 1~2 degrees higher than the ambient temperature when the device warmed up

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Rev. 3.0 | Jun.2023

Keypad operation(continued)

Page 2 (output limit page)

5

Page 2

On page 1, click to switch to page 2

5.1

Output min. limit On the first row of page 2

(R>)

5.2

Set output min.

limit (R>)

On page 2 Number key 0~9 / the black key (decimal point) + the red key (enter/ok)

“R>” default value is “0”, i.e. any SP that is greater than “0” is
allowed If the current SP < limit value
Output (PV) will be forced to be the latter and with a mark “*” on display near “PV”.

5.3

Set output min.

limit (R>) unit

5.4

Back to page 0

6

Device info.

(1/3)

6.1

Device info.

(2/3)

6.2

Device info.

(3/3)

6.3

Back to page 0

On page 2
Click , unit changes in the order of “” “K(k)” “M(M)”

Weight of the number key changes according to “unit”.

– After setting a new limit value, click again to return to page 0;
– Click back to page 0.

Device information
On page 0 Use combination keys ” + number key ” to view device info. (1/3):
– Device Type/order code – Step (STP) – Tolerance (TOL) – Output range (RGE) In the state of item 6: Click : – T.C.R(TCR) – Calibration temperature (C/T) – Rated power (PWR) – Operating Temperature Range (OTR) In the state of item 6.1: Click : – Hardware version (H/W) – Firmware version (H/W) – Serial Number (S/N) – Production date (PRD), yyyymmdd In the state of item 6.2: Click or wait about 30 sec.

Note: When device info. is displaying, some AT commands cannot be executed in real-time. Screen demo of device info. (1/3):
Screen demo of device info. (2/3):
Screen demo of device info. (3/3):

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Rev. 3.0 | Jun.2023

Keypad operation(continued)

Auto-scanning

7

Auto-scanning

On page 0

(1/2)

Use combination keys ” + number key ” to

enter auto-scanning setting menu:

– Enable auto-scanning (EN), click to switch between “ON” and “OFF”

– Loop (LOP), click to switch between “YES” and “NO”

– Scanning direction (DIR), click to switch between “+, INC (increasing)” and “-, DEC (decreasing)”

More flexible scanning functions can be realized via AT commands

7.1

Auto-scanning

(2/2)

– Scanning period (T), use number

keys to enter a value from 1 s to 99 s.

–

Scanning steps (R), use number keys + (decimal point) to enter a value

Units of R, MIN, and MAX are

– Scanning range low (MIN), same as

non-editable, but they can be

changed automatically based on

above

the current (setting) value.

– Scanning range high (MAX), ), same

as above

7.2

Save & activate the Click to save the current item and activate The is used to indicate the

following item

the following item

active row which is editable.

7.3

Set initial value for

scanning

– Set it via SP on page 0 before autoscanning is enabled (recommended)
– Set it on page 0 after auto-scanning is enabled (SP unit is fixed to “”)
– via AT command

By default, the scanning initial value is the current SP.

7.4

Pause/Start

Click to pause/start auto-scanning during the operation on page 0

(image) A “*” before SP to indicate SP is modified by auto-sacnning; a “||” means “pause of auto-scanning”

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Rev. 3.0 | Jun.2023

Keypad operation(continued)

User calibration

8

User calibration

On page 0

Use combination keys ” + number key ” to

enter the user calibration setting menu.

8.1

Exit

Hold for 1.5 sec. to return to the main page.

8.2 Enable(EN)

Click to switch between “ON” and “OFF”. – “ON”: use user calibration data as the

reference – “OFF”: use factory calibration data as

8.3 Record calibration temperature (C/T) ­ 1/28

reference – Click to load a value from the
built-in temperature sensor (recommended)

– Click again to cancel, or click to

confirm.

8.4

Save & page down Click to save the current item and turn to

next page

8.5 Record min. output (RMIN ­ 2/28)

– Set the reference value via keypad (refer to 3.1),
– Or click to load a default value and

8.6 Record calibration point 0 (R00 ­ 3/28)

click to confirm. – Set the reference value via keypad
(refer to 3.1), – Or click to load a default value and

click again to cancel/click to

8.7 Record calibration point 1 (R01 ­ 4/28)

confirm. – Set the reference value via keypad
(refer to 3.1),

– Or click to load a default value and

click again to cancel/click to

…

Record calibration

Point 2 ~ point 23

confirm. …

8.8 Record calibration max. output(RMAX ­ 27/28)

– Set the reference value via keypad (refer to 3.1),
– Or click to load a default value and click again to cancel/click to

confirm.

8.9 Record calibration Set the date via keypad number keys. A string

date

of 8 bytes is free for saving.

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Connect reference multimeter probes to QR10 binding posts first. A 4-wire connection is recommended. All editing items were saved before exit. For FW v5.93~v5.96, need to reboot the device after new setting. On main page row 1, F indicates “factory calibration data is in application” while U stands for “user calibration data is in application”. Can also set the value via keypad (refer to 3.1). Still can edit (set a new value) after confirmation.
Default values can be used to check the “healthy” of the device as relays get aged.
R02~R23, all the same operation as 8.5~8.7 mentioned. For > 1 M value, may need to wait several minutes until it gets stable.
After the save & page down operation (8.4), return to the main page and the new setting take effect immediately (for FW v5.93~v5.96, need to reboot the device)
Rev. 3.0 | Jun.2023

AT command set
Users can remotely control the instrument and check device information via serial COM software.

Driver IC Driver installation

Configuration WCH CH340
Turn on the device, and connect it to PC via a USB type-C cable. Select the driver to install manually or let the PC do auto-scanning for installation.

Driver link
After successful installation, the following information can be found through Device Manager (Windows)

Baudrate & settings End mark (EOT)

115,200 bps, 8 data bits, no parity, and 1 stop bit r or n

Necessary for each command.

AT Command Set Table

No. Description

Instruction

Default

(need to add r’ orn’ at the end of

Unit

each command)

Basic instructions

Example (communication log.)

1

Get SP

2 Set SP

AT+USER.SP? AT+USER.SP=

3 Set SP

AT+USER.SP+=

(Increasingly)

4 Set SP

AT+USER.SP-=

(Decreasingly)

TX: AT+USER.SP?

RX: +USER.SP=1.0000

TXAT+USER.SP=2

RX+OK.

RXSP(R)=2.000

PV(R)=2.009

UMax(V)=1.5

RLimit(R)=0.000

InnerT(C)=27.68

Initial status: SP=2.0

TXAT+USER.SP+=1

RX+OK.

RXSP(R)=3.000

PV(R)=3.014

UMax(V)=1.8

RLimit(R)=0.000

InnerT(C)=27.68

Initial status: SP=3.0

TXAT+USER.SP-=1

RX+OK.

RXSP(R)=2.000

PV(R)=2.009

UMax(V)=1.5

RLimit(R)=0.000

InnerT(C)=27.68

5 Get PV

AT+USER.PV?

TXAT+USER.PV? RX+USER.PV=10.024

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AT Command Set Table(continued)

6 Get safety

AT+USER.RLIMIT?

output limit

7 Set safety

AT+USER.RLIMIT=

output limit

8 Get internal

AT+USER.T_SENSOR?

temperature

User calibration

9 Get calibration AT+UCAL.EN? data reference source

10 Enable/disable AT+UCAL.EN=<‘1’/’0′> user calibration data

11 Get user

AT+UCAL.INFO?

calibration

info.

12 Get T.C.R

AT+DEV.TCR?

13 Get device type AT+DEV.TYPE?

14 Get production AT+DEV.PROD? date

15 Get serial number

AT+DEV.SN?

16 Get HW version

AT+DEV.HW?

17 Get FW version

AT+DEV.FW?

Device info. ppm

TX: AT+USER.RLIMIT? RX: +USER.RLIMIT=0.0000 TXAT+USER.RLIMIT=10 RX+OK. RXSP(R)=2.000
PV(R)=10.024 UMax(V)=3.4 RLimit(R)=10.000 InnerT(C)=27.59 TXAT+USER.T_SENSOR? RX+USER.T_SENSOR=27.66
TXAT+UCAL.EN? RX+UCAL.EN=0
1′: User calibration data activated0′: Factory calibration data activated TXAT+UCAL.EN? RX+UCAL.EN=0 1′: Activate user calibration data0’: Activate factory calibration data TXAT+UCAL.INFO? RX+UCAL.INFO:
USEN =0 DATE=20221025 TEMP=27.13 MAX(cali)=8553299 MAX(math)=8553284 MIN =1.0120 CH0=2.1000 CH1=3.0500 CH2=4.9900 …
TXAT+DEV.TCR? RX+DEV.TCR=25 TXAT+DEV.TYPE? RX+DEV.TYPE=QR101B-AM-1R TXAT+DEV.PROD? RX+DEV.PROD= TXAT+DEV.SN? RX+DEV.SN=00000127 TXAT+DEV.HW? RX+DEV.HW=5.1N TXAT+DEV.FW? RX+DEV.FW=5.963KS

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Example of use
Example 1 (Power on and set SP to 1k via keypad)
Step 1: Press and hold the red button until the screen appears, release the button and wait to enter the main page (page 0).
Step 2 (optional): Click on the black button to switch SP/PV units. Refer to Keypad Operation 3.3.
Step 3: If the SP/PV unit is “”, click “1”, “0”, “0”, and “0” and then click the red button to confirm; If the SP/PV unit is “K”, click “1” and then click the red button to confirm; If the SP/PV unit is “M”, click “0”, the black button (decimal point), “0”, “0 “, “1”, and finally click the red button to confirm.
Example 2 (USB-Serial port setting SP to 10k)
Step 1: Configure the serial port communication baud rate and other settings correctly.
Step 2: Send “AT+USER.SP=100000rn”

Self-check

Item Display message

1

Show “VB<*V”

when powered up

2

ERR.01

3

ERR.02

Action
Refuse working if battery voltage <3.6 V. Should recharge it soon. “*” represents the current battery voltage. Click the red key to shut down. Please contact the manufacturer for a solution. Click the red key to shut down. Please contact the manufacturer for a solution.

Maintenance (Important)
o Do not overload. o Do not use in humid environments and avoid water ingress. o Please keep the shell clean (sweat stains may penetrate the surface paint layer and
chemically react with brass to produce black rust spots) o Storage conditions, the built-in lithium battery shelf life of about 10 months, it is
recommended to replenish the battery every 8 months. o The contact on- resistance of mechanical relays and base resistors may age due to use, so
annual calibration is recommended.

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Appendix 1 (sample calibration certificate)

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Eastwood Instruments – Always do better.
For more information: www.eastwood.tech
Protected by CN patents: ZL202122003046.7 ZL202130497759.6
©2021-2023 Eastwood Instruments. Specifications subject to change without notice.
This document was written and published by Channing Chang. Modification of this document is not permitted without written permission from Eastwood Instruments.

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References

• The domain name ucal.info is for sale | Dan.com
• Eastwood Instruments – Always do better.
• USB to Serial Port Chip CH340 - NanjingQinhengMicroelectronics
• 产品中心 - 南京沁恒微电子股份有限公司

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