Com­pa­ring phy­si­cal lay­er CAN dia­gno­stic devices

You have pro­blems with your bus, in your sys­tem or at your customer’s site. You have to mea­su­re and stop gues­sing – what you need at this point is a dia­gno­stic device.

The mar­ket is con­fu­sing, they try to decei­ve with fal­se pro­mi­ses but giving no real com­pa­ri­son. We try it and compa­re the GEMAC devices. For this com­pa­ri­son, we take the three devices that do mea­su­re at the phy­si­cal lay­er. CANalarm has spe­cial fea­tures, which has not­hing to do with phy­sics and CAN­vi­si­on is as pro­to­col moni­tor working on logi­cal lay­er only. The­r­e­fo­re the­se two pro­ducts are not lis­ted in this comparison.

A table like this with fea­tures can only be some kind of hint. Fea­tures dif­fer from device to device, even when both of them have it. The­re may be a dif­fe­rent under­stan­ding of a fea­ture or a dif­fe­rent expec­ta­ti­on. Plea­se open a ticket within the sup­port area if the­re are spe­cial ques­ti­ons run­ning in your mind.

In this artic­le, we go even deeper into the ago­ny of choice and make recommendations.

revi­sed and updated March 2017



In Gene­ral

Bus sys­tems (CAN, CANopen, Device­N­et, SAE J1939)
Auto­ma­tic baud rate scan /​Node or Iden­ti­fier Scan ● / ● ● / ● ● / ●
Export data
Print func­tion Screen­shot or Export
Mana­ge measurements

Online Moni­to­ring

Dis­play bus status
Dis­play bus traf­fic load ● with progress
Dis­play error­frame coun­ter (abso­lu­te /​per second) ● with progress
Dis­play optio­nal CAN sup­p­ly voltage ● with progress
Dis­play shield voltage ● with progress

Abso­lu­te mea­su­re­ments CAN_​H /​CAN_​L against V-

Com­mon mode voltage
CAN Level abso­lu­te /​dif­fe­ren­ti­al ● / ●

Bus wiring

Cable length
Ter­mi­na­ti­on resistors
Loop resis­tance (bus, power supply)

Node Mea­su­re­ment

Bus sys­tem CAN with ID scan
Bus sys­tem CANopen with NodeID-Scan
Bus sys­tem Device­N­et with MacID-Scan
Bus­sys­tem SAE J1939 with Sourceadress-Scan
Qua­li­ty level mea­su­re­ment of all nodes
Qua­li­ty level, dis­tur­ban­ce-free vol­ta­ge ran­ge, edge steepness
Dis­play oscil­lo­gram, dif­fe­ren­ti­al signal, phy­si­cal or logi­cal decoded
Dis­play oscil­lo­gram, abso­lu­te signal (CAN_​H /​CAN_​L vs. refe­rence ground)

Pro­to­col Monitor

Send CAN messages
Recei­ve CAN messages
Sym­bo­lic decode CAN messages
Trig­ger /​Such­funk­tio­nen
Trace CAN mes­sa­ges (con­fi­gura­ble start- /​stop conditions)
Recei­ve /​decode CANopen messages
Recei­ve /​decode SAE J1939 mes­sa­ges as well as ISOBUS and NMEA 2000

Online Trig­ger

Recor­ding time max. 1 week unli­mi­t­ed max. 10 years
Gau­ges 4x phy­si­cal + 4x logical
E‑Mail war­ning
Con­trol point access (SNMP)
Access with brow­ser (HTML5, mobi­le devices)
Error out­put
Dis­plays oscil­lo­gram on sin­gle measurement
Tone signal on trigger


Func­tion unsupported
in basic ver­si­on included
can be unlo­cked by license
included in license