Each SCM5B45 frequency input module provides a single channel of frequency input which is isolated and converted to a high-level analog voltage output. This voltage output is logic switch controlled, which allows these modules to share a common analog bus without the requirement of external multiplexers.

The frequency input signal can be a TTL level signal or a zero-crossing signal. Terminal 3 on the field-side terminal block is the "common" or ground connection for input signals. A TTL signal is connected from terminal 2 to terminal 3, while a zero-crossing signal is connected from terminal 4 to terminal 3. Input circuitry for each of the signal types has hysteresis built in. An input signal must cross entirely through the hysteresis region in order to trigger the threshold comparator.

A 5.1V excitation is available for use with magnetic pick-up or contact-closure type sensors. The excitation is available on pin 1 and the excitation common is pin 3.

The SCM5B modules are designed with a completely isolated computer side circuit which can be floated to ±50V from Power Common, pin 16. This complete isolation means that no connection is required between I/O Common and Power Common for proper operation of the output switch. If desired, the output switch can be turned on continuously by simply connecting pin 22, the Read-Enable pin, to I/O Common, pin 19.

A special circuit in the input stage of the module provides protection against accidental connection of power-line voltages up to 240VAC.
  • Accepts Frequency Inputs of 0 to 100kHz
  • Provides High-Level Voltage Outputs
  • TTL Level Inputs
  • 1500 Vrms Transformer Isolation
  • ANSI/IEEE C37.90.1 Transient Protection
  • Input Protected to 240VAC Continuous
  • ±0.05% Accuracy
  • CSA Certified, FM Approved, CE and ATEX Compliant
  • Mix and Match SCM5B Types on Backpanel
Frequency Input Modules

SCM5B45 Devices


Part Number Input RangeOutput RangeZero Crossing HysterisisMechanical FormatIsolation VoltageIsolation Type
0 to 500 Hz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 500 Hz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 1 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 1 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 3 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 3 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 5 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 5 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 10 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 10 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 25 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 25 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 50 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 50 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 100 kHz 0 to +5 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 100 kHz 0 to +10 V ±20mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 500 Hz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 500 Hz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 1 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 1 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 3 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 3 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 5 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 5 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 10 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 10 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 25 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 25 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 50 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 50 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 100 kHz 0 to +5 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way
0 to 100 kHz 0 to +10 V ±400mV Modular plug-in-board 1500 Vrms Transformer 3-way

Frequently Asked Questions


Can you make SCM5B45-08 with +/-5V output?
This requires a custom designed module; we typically offer a single module custom solution with unit pricing for the required 10 piece minimum order and 7-8 week lead time. Please contact Dataforth at (520) 741-1404 if your application requires a non-standard range not offered in our product catalog.

Often times, a two module solution can help achieve the required output range. In the aforementioned case of the 5B45-08, one would connect its output to a 5B49-01 thus yielding a +/-5V output. Note that the accuracy specs will be additive across the two modules.

Can Dataforth provide calibration reports for modules I purchased?
Yes we can provide calibration reports for the modules that you purchased.

You can either
a) visit https://www.dataforth.com/TestDataReport.aspx to search for Test Report Datasheets by Serial Number or
b) you can send us a list of model numbers and their serial numbers to support@dataforth.com

Analog Devices announced a last time buy and discontinuance of their signal conditioning modules. Can I replace them with Dataforth signal conditioning modules?
Yes, in general, Dataforth signal conditioning modules are a direct replacement for all Analog Devices signal conditioning modules. e.g. "SCM5B35-xx: Linearized 4-Wire RTD Input Modules" will replace Analog Devices "5B35: Isolated 4 Wire RTD Input Signal Conditioning Module".

Please note that Dataforth signal conditioning modules are RoHS II compliant.

How do I connect the 5B45 to the field signal?
For Zero Crossing, connect the signal to EXC+ and the return to IN-.

For TTL, connect the signal to IN+ and the return to IN-.


Is the calibration of Dataforth modules traceable to NIST standards?
Yes, calibration of Dataforth modules is traceable to NIST standards.

What is the recommended power supply for Dataforth SCM5B and 8B modules?
The recommended power supply for the Dataforth SCM5B and 8B modules are the linear power supplies in our SCMXPRT/SCMXPRE series. The SCMXPRT/SCMXPRE power supplies output 5V and have options for 1A output current (SCMXPRT-001) or 3A output current (SCMXPRT-003).

The SCMXPRE series is identical to its SCMXPRT counterpart, but is configured for European voltage standards.

The SCMXPRT-001/SCMXPRE-001 both have the option for DIN rail mounting as well (SCMXPRT-001D/SCMXPRE-001D).

Other power supplies that meet that power requirements of the SCM5B and 8B modules can be used as well, but it is strongly recommended to use a linear power supply rather than a switch-mode power supply. Switching power supplies can add noise artifacts to the output of your modules.

How do I convert an RMS voltage to its corresponding peak voltage?
To convert an RMS voltage to its corresponding peak voltage, you simply take the RMS voltage value and multiply it by the square root of 2, or roughly 1.414.

For example, 1500Vrms corresponds to a peak voltage of 1500 * 1.414 = 2121 Vp

Will the isolation on the SCM5B modules support a discharge of 1500VDC without damaging anything connected to the output?
Yes, the SCM5B modules are isolated up to 1500 Vrms, which means that if the common mode voltage between the field side and system side is limited to 1500Vrms, the device will be protected.

However, the input protection for SCM5B modules (i.e., the voltage across the +IN and -IN input terminals) is 240Vrms max.

Do you have any SCM5B modules with a 50kHz bandwidth?
None of our standard SCM5B modules have a 50kHz bandwidth. However, it is possible to order a custom SCM5B module with 50kHz bandwidth. Keep in mind that new customs require a 10 pc minimum order and are subject to extra design fees.

Do you have an MTBF figure for the SCM5B39? What are the main failure modes?
The failure rate calculations for our SCM5B modules can be found in our application note AN503: https://www.dataforth.com/catalog/pdf/an503.pdf

There are no dominant failure modes.

What is the required resistance for jumpers J1 through J4 on my SCM5B backpanel?
J1-J4 on the SCM5B backpanels are jumper cables, so they should have 0 ohm resistance.

On the SCM5B modules, what is the purpose of pin 18 (Vin), why is it tied to pin 20 (Vout)? Doesn't Vout provide the output by itself?
Vout is used with input modules, which are all the SCM5B models except for the SCM5B39 and SCM5B49. Vin is used for output modules, SCM5B39 and SCM5B49.

The reason for doing this is because input modules acquire a signal from the field side, and then output a corresponding signal to the system side. On the contrary, output modules acquire a signal from the system side, and then output a corresponding signal to the field side. Since SCM5B backplanes are designed for all channels to accommodate either an input or an output module, the terminal/pin that you would normally get your output signal from if you were using an input module is the same terminal/pin that you would be feeding your input signal to if you were using an output module.

If I purchase a backplane with no CJC, will I still be able to use modules that require the CJC enable jumper to be installed?
Yes. Backplanes with no CJC will still come with the CJC enable installed on the backplane.

Do SCM5B modules with outputs scaled up to 10V have separate power requirements from their 5V counterparts?
No, all SCM5B modules have the same power requirements (5VDC) regardless of their I/O specifications. The power supply current draw of different products in the SCM5B line may vary.

I just received an SCMPB01 back panel. How should I configure jumpers J1 through J4 for my application?
The factory configuration for jumpers J1 through J4 is the optimal configuration for most applications. If for some reason this jumper configuration will not work/is not working in your application, see our application note AN502 "Ground Connections and Host System Interfaces" for other valid jumper configurations and what situations you would use them.

Can I use an SCM5B module with my OM5-BP-SKT-C?
Yes, any of our SCM5B modules are able to be mounted and operated on Omega's OM5-BP-SKT-C board.

Do I need to purchase the SCMXCJC with my SCMPB03?
No, the SCMPB03 comes with the CJC built into the backpanel.

Can I use the SCMXBEFE and SCMXSE accessories to make my SCMPB01/2 DIN rail mountable?
No, converting any of the 16 channel SCM5B backplanes to something DIN rail mountable is a much more involved process than the SCMPB03/04. If you would like a 16 channel SCM5B backplane that can mount on a DIN rail you must purchase an SCMPB01-2, SCMPB01-3, SCMPB02-2 or SCMPB02-3.

How does the load resistance of a module affect the noise at the output?
Noise at the output of a module is independent of load resistance.

If the input range of my signal conditioner is -1V to +1V and the output range is 0 to 10V, does this mean that it ignores polarity?
A signal conditioner with these I/O ranges does not mean that the module ignores the polarity of your voltage input. The output of voltage input modules are scaled linearly, meaning an input of -1V would correspond to an output of 0V, an input of 0V would correspond to an output of 5V, an input of +1V would correspond to an output of 10V, and so on.

Is the SCMXPRT-003 DIN rail mountable?
The SCMXPRT-001 has an option for DIN rail mounting (part number: SCMXPRT-001D) but the SCMXPRT-003 does not. Instead, it can be mounted on the SCMXRK-002 which is a 19 inch metal rack for mounting the SCMXPRT-003 as well as various Dataforth backpanels and the SCMXIF interface board.

Should I ground my sensor wire shield to the 10-32 ground post on the SCMPB01?
It is not recommended to ground the sensor wire shield to the 10-32 ground post on the SCMPB01 because that is the system side ground, while the sensor wire is on the field side. The sensor wire shield should be grounded to the field side ground, which varies based on the signal conditioner you are using. Please see the "Shield Grounding" application note for more information.

Is the SCM5B40-06 sensitive to being soldered into a board? Would soldering it damage the part?
We do not recommend soldering the SCM5B pins to a board as it could potentially damage the module. Soldering the pins would also void the warranty.

Many sockets are available which accept the mounting pins. TE Connectivity / AMP part number 50865-5 is an example of these sockets and any equivalent part will work as well.
Was this content helpful?    Yes / No
Model NumberInput RangeOutput RangeBandwidthSensor TypeStatus*Comments
SCM5B45-1153
0KHZ TO 4KHZ-5V TO +5V FREQUENCY INPUTPR 
SCM5B45-1163
0KHZ TO 6KHZ0V TO +5V FREQUENCY INPUTQU< 100ms Response Time
SCM5B45-1164
0KHZ TO 15KHZ0V TO +5V FREQUENCY INPUTPR< 100ms Response Time
SCM5B45-1167
0HZ TO 100HZ0V TO +10V FREQUENCY INPUTQU< 1.7% Accuracy
SCM5B45-1194
0HZ TO 1KHZ0V TO +5V FREQUENCY INPUTPR25ms Response Time
SCM5B45-1206
0HZ TO 30HZ0V TO +5V FREQUENCY INPUTPR.55 Sec Response Time, 1.0V hysteresis
SCM5B45-1210
0HZ TO 150HZ0V TO +5V FREQUENCY INPUTQU 
SCM5B45-1251
0 TO 100HZ0V TO +5V FREQUENCY INPUTPR 
SCM5B45-1396
0Hz TO 3000Hz0V TO +5V FREQUENCY INPUTPR20mVp-p Minimum Zero Crossing Input
SCM5B45-1423
0Hz TO 1600Hz0V TO 5V FREQUENCY INPUTPR20mVp_p Minimum Zero Crossing Input
SCM5B45-1429
0Hz TO 1000Hz0V TO 5V FREQUENCY INPUTPR20mVp_p Minimum Zero Crossing Input
SCM5B45-1430
0Hz TO 3000Hz0V TO 5V FREQUENCY INPUTPR20mVp_p Minimum Zero Crossing Input
SCM5B45-1431
0Hz TO 5000Hz0V TO 5V FREQUENCY INPUTPT20mVp_p Minimum Zero Crossing Input
SCM5B45-1470
0Hz TO 569Hz0V TO +10V FREQUENCY INPUTPR 
SCM5B45-1471
0Hz TO 1500Hz0V TO +10V FREQUENCY INPUTPR 
SCM5B45-1480
0Hz TO 9400Hz0V TO +10V FREQUENCY INPUTPR90ms response time
SCM5B45-1524
0KHZ TO 10KHZ-5V TO +5V FREQUENCY INPUTPR 
SCM5B45-1525
0KHZ TO 15KHZ-5V TO +5V FREQUENCY INPUTPR 
SCM5B45-1598
0KHZ TO 25KHZ-5V TO +5V FREQUENCY INPUTPR+/-400mV Input hysteressis
SCM5B45-1606
0HZ TO 800HZ-5V TO +5V FREQUENCY INPUTPR+/-400mV Input hysteressis
SCM5B45-1607
0KHZ TO 40KHZ-5V TO +5V FREQUENCY INPUTPR+/-400mV Input hysteressis
SCM5B45-1610
0KHZ TO 5KHZ-5V TO +5V FREQUENCY INPUTPR+/-400mV Input hysteressis
SCM5B45-1658
0KHZ TO 2.5KHZ-5V TO +5V FREQUENCY INPUTPR+/-400mV Input hysteressis
* ... Status Codes: PR = Production, PT = Prototypes, QU = Quoted