Datasheet

CMM-2CH-10A60V

Description

This module offers two separately isolated channels for current measurements over a wide range from 1µA to 10A. Ethernet and CAN-FD are available for communication. Current is measured in six automatically selected ranges as listed in the table below:

Range	Lower End	Upper End	Lower Threshold	Upper Threshold
0	1µA	100µA	-	110µA
1	100µA	1mA	90µA	1.1mA
2	1mA	10mA	0.9mA	11mA
3	10mA	100mA	9mA	110mA
4	100mA	1A	90mA	1.1A
5	1A	10A	900mA

Mechanical details

Module dimensions	160mm x 100mm (Eurocard)
19” specification	5 TE x 3 HE

Ambient conditions

Ambient operating temperature	5…50°C
Storage temperature	-20…70°C
Humidity	5…80% noncondensing

Current Paths

	Min	Typ	Max	Unit	Remarks
DC current			10	A
Worst case DC current			16	A	25° Ambient Temperature with airflow >2m/s
Maximum measurable current			16	A
Single pulse current			50	A	max. 100ms
DC Current per pin on backplane connector			6	A
Voltage across current in/out when module is off			60	V
Leakage current @ OFF			100	µA	60V across module , temperature 25°C
Isolation rating	-150		150	V	Maximum allowed voltage difference between module supply and current path
Reverse current continuous			4	A
Reverse current single pulse			30	A	Max. 100ms

Module Supply

Connect the power supply between +24V-CON and GND-CON. It is strongly recommended not to use the DUT power supply to power the CMM. Please note that the current path is interrupted when the module is unpowered.

	Min	Typ	Max	Unit	Remarks
Supply voltage	20	24	26	V	+24V-CON to GND-CON
Supply current (Ethernet port active)		110		mA	Supply voltage = 24V
Supply current (Ethernet port inactive)		95		mA	Supply voltage = 24V
Supply inrush current		3		A	Inrush current for < 1ms @ dU/dt ≈ 20V/ms, 24V supply

Typical inrush current waveform

Module supply voltage (green) and supply current (red)

DC Accuracy and resolution

The module’s accuracy is verified for DC currents during in-house calibration. The module may of course be re-calibrated. See chapter "Calibration Recommendation" for more info.

	Typ	Max	Unit	Remarks
Accuracy uncalibrated	0,5	2	%	% of respective range’s maximum current
Accuracy calibrated	0,2	1	%	% of respective range’s maximum current
Resolution range 0	40,4		nA
Resolution range 1	404		nA
Resolution range 2	4,04		µA
Resolution range 3	40,3		µA
Resolution range 4	403		µA
Resolution range 5	4,03		mA

DC Voltage Drop

The following table lists the voltage across the module’s current input and output pins for specific current values. These are typical values, measured at room temperature at the connector pins of one channel.

	Typ	Unit	Remarks
Drop @ 100µA	50	mV	Range 0
Drop @ 1mA	50	mV	Range 1
Drop @ 10mA	55	mV	Range 2
Drop @ 100mA	60	mV	Range 3
Drop @ 1A	60	mV	Range 4
Drop @ 10A	110	mV	Range 5
Drop @ 16A	180	mV	Range 5

Ethernet

The module supports 10Mbit/s and 100Mbit/s Ethernet on the RJ45 front connector. Default IP: 192.168.222.1

CAN-FD

The module provides a CAN-FD interface on the front via a 9-pin D-Sub connector as well as on the backplane connector.

Supported nominal bit rates	500 kbit/s, 1 Mbit/s
Supported data bit rates	1 Mbit/s, 2 Mbit/s, 4 Mbit/s
Default settings	1 Mbit/s nominal, 4 Mbit/s data, no bit rate switch

120Ω on-board termination is available via jumper. On-board termination is only recommended if a single module is used without further devices connected via CAN. If multiple devices are connected via CAN, it is recommended to use external termination on both ends of the CAN harness. This avoids problems when modules are swapped or replaced.

Backplane connector

Connector type: Harting 09041326921 Please make sure you use all connector pins for current in / current out. A backplane-pcb is available for easy connection with just two pins per current measurement channel.

Pin	Signal	Pin	Signal
A2	+24V module supply	C2	0V module supply
A4	CAN Low	C4	CAN High
A6	Channel 0 Current In	C6	Channel 0 Current In
A8	Channel 0 Current In	C8	Channel 0 Current In
A10	Channel 0 Current In	C10	Channel 0 Current In
A12	Channel 0 Current Out	C12	Channel 0 Current Out
A14	Channel 0 Current Out	C14	Channel 0 Current Out
A16	Channel 0 Current Out	C16	Channel 0 Current Out
A18	Channel 0 Current Out	C18	Channel 0 Current Out
A20	Channel 1 Current In	C20	Channel 1 Current In
A22	Channel 1 Current In	C22	Channel 1 Current In
A24	Channel 1 Current In	C24	Channel 1 Current In
A26	Channel 1 Current Out	C26	Channel 1 Current Out
A28	Channel 1 Current Out	C28	Channel 1 Current Out
A30	Channel 1 Current Out	C30	Channel 1 Current Out
A32	Channel 1 Current Out	C32	Channel 1 Current Out

Calibration Recommendation

IRS recommends a recalibration within 2 years.

The calibration should be performed for each channel at multiple calibration points for all 6 ranges. IRS recommends measuring at least the following currents.

Range	Calibration Points
100 uA	20 uA, 40 uA, 60 uA, 80 uA, 100 uA
1 mA	0.2 mA, 0.4 mA, 0.6 mA, 0.8 mA, 1 mA
10 mA	2 mA, 4 mA, 6 mA, 8 mA, 10 mA
100 mA	20 mA, 40 mA, 60 mA, 80 mA, 100 mA
1 A	0.2 A, 0.4 A, 0.6 A, 0.8 A, 1 A
10 A	2 A, 4 A, 6 A, 8 A, 10 A

Current values should be captured with the function (IRS.CMM-xCH.Shared.Gateway).GetMinMaxAverage. This function returns the value averaged since last read.

Before capturing a valid value, enable the calibration current, perform a dummy read and wait 100 ms.

The fluctuations of the power source used should not exceed 0.1% of the nominal value.

Revision History

Revision	Date	Author	Change Log
1.0	01.08.2023	madi1	Initial Release
1.1	11.10.2023	madi1	Add more values in section "Current Path"
1.2	13.12.2024	madi1	Update DLL name in section "Calibration Recommendation". Add recommendation for external CAN termination.
1.3	17.12.2024	miho1	Update supply current and DC voltage drop values
1.4	29.01.2025	madi1	Refactor datasheet for gitbook