"gegen Masse(potential )" is similar to standardized term "gegen Erde".

Area Earthing and protection against electric shock / Voltages and currents
IEV ref 195-05-06
en
voltage to earth during an earth fault
voltage to ground during a ground fault (US)voltage between a specified point and reference earth, for a given location of the earth fault and a given value of earth-fault current
:
de
Spannung gegen Erde bei Erdschluss, f
http://www.electropedia.org/iev/iev.nsf/display?openform&iev...

Domain  Electronics and electrical engineering, Statistics  
Domain note  dispositifs électriques et magnétiques 

 de 
Term Masse 
Reliability 3 (Reliable) 
Term Ref. IEV 151-1-9

Term Körper 
Reliability 3 (Reliable) 
Term Ref. IEV 151-1-9

Term Chassis 
Reliability 3 (Reliable) 
Term Ref. IEV 151-1-9

 en 
Definition the conductive body whose potential is taken as reference  
Definition Ref. IEV 151-1-9  

Term frame 
Reliability 3 (Reliable) 
Term Ref. IEV 151-1-9

Term chassis 
Reliability 3 (Reliable) 
Term Ref. IEV 151-1-9
http://iate.europa.eu/SearchByQuery.do?method=searchDetail&l...

Arbeitsplatzleuchte nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Trägerplatte (TP) der Streuscheibe (SS) mit einer leitfähigen Schicht versehen ist, die mit Massepotential in gut leitender Verbindung steht.

Workplace luminaire according to one of the preceding claims, characterized in that the backing plate (TP) of the diffusing screen (SS) is provided with a conductive coating which is connected to frame potential in an effectively conducting fashion.
http://context.reverso.net/übersetzung/deutsch-englisch/Arbe...

Figure 2: Cell to frame potential showing the PID affected modules. [6]
https://www.researchgate.net/publication/323202459_Effects_o...

(10V to 60V Models) Output Ratings - ...
PDF https://www.testwall.com › 2015/09 › X...
<500 Ohm. <1 kOhm. Isolation, all program and readback lines. 300 Vdc with respect to chassis potential or negative output ...
Series 2268 850W DC Power Supplies
PDF https://www.tek.com › datasheet › 2268-...
19.12.2014 · Isolated I/O Lines: 600V, with respect to chassis potential. 1500V, to either output. SHUTDOWN CONTROL (isolated ...
Series 2268 850-Watt DC Power Supplies Specifications
PDF download.tek.com › document
readback lines. Non-isolated I/O lines: Isolated I/O lines: 500 V, with respect to chassis potential. 600 V, with respect to chassis potential.
(copied from the Google search showing a lot of PDFs, impossible to copy content and links only by smartphone.)

The choice between "frame" and "chassis" depends on the shape and execution. Please note that in most cases the frame or chassis must be earthed (grounded) acc. electo technical rules, resulting in no potential difference to earth (ground)



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Note added at 4 days (2018-10-16 10:34:43 GMT) Post-grading
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How the frame, chassis or body must be earthed or not can been seen on different pages, e.g.

In an electrical installation an earthing systemor grounding system connects specific parts of that installation with the Earth's conductive surface for safety and functional purposes. The point of reference is the Earth's conductive surface. The choice of earthing system can affect the safety and electromagnetic compatibility of the installation. Regulations for earthing systems vary considerably among countries, though many follow the recommendations of the International Electrotechnical Commission. Regulations may identify special cases for earthing in mines, in patient care areas, or in hazardous areas of industrial plants.
:
https://en.m.wikipedia.org/wiki/Earthing_system

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Note added at 4 days (2018-10-16 13:30:36 GMT) Post-grading
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N this article is specified by "conductive parts of electrical equipment", designing all accessible conductive metal parts of housings, enclosures and conductively connected frames.



The different earthing systems are shown under

Characteristics of TT, TN and IT systems

General rules of electrical installation designConnection to the MV utility distribution networkConnection to the LV utility distribution networkMV and LV architecture selection guide for buildingsLV DistributionEarthing schemesEarthing connectionsDefinition of standardised earthing schemesCharacteristics of TT, TN and IT systemsSelection criteria for the TT, TN and IT systemsChoice of earthing method - implementationInstallation and measurements of earth electrodesThe installation systemDistribution switchboardsCables and buswaysHarmonic currents in the selection of busbar trunking systems (busways)External influences (IEC 60364-5-51)Definition and reference standardsClassificationList of external influencesProtection provided for enclosed equipment: codes IP and IKProtection against electric shocks and electrical firesSizing and protection of conductorsLV switchgear: functions and selectionOvervoltage protectionEnergy Efficiency in electrical distributionPower Factor CorrectionPower harmonics managementCharacteristics of particular sources and loadsPhotoVoltaic (PV) installationResidential premises and other special locationsElectroMagnetic Compatibility (EMC)Measurement

Contents [hide] 

1- TT system
....1.1- Main characteristics
2- TN system
....2.1- Main characteristics
3- IT system
....3.1- Main characteristics
http://www.electrical-installation.org/enwiki/Characteristic...

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Note added at 5 days (2018-10-17 14:41:18 GMT) Post-grading
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I cite Stephen: Technicians call it ground whether it is connected to earth or not. During computer work you "ground" yourself by connecting to the chassis".

This statement is potentially dangerous. As electrician and engineer I learned to distinguish accurately between real earth (PE) and virtual earth. In German we have to different terms "Masse" for all metal enclosures and frames, and "Erde" for all conductive parts connected to the star point or the real earth, like the PE conductor. In English we can distinguish between virtual and real earth or between the frame or enclosure and the earth. This distinction is made by international and UL standards as well and very important, in order not to mismatch parts or to endanger beings.

The context refers to electronic components with floating potential, i.e. not connected to the grounding conductor. This explains why it is possible the have voltages between its terminals and the enclosure ("Masse") independent on its potential. This is possible with galvanic separation, e.g. using optocouplers or similar. All floating potentials from enclosures have to be connected to the real earth prior to work on components in order to avoid discharges.

Summary: We have a) an electronic component, b) an insulated enclosure (housing) and b) the power supply with PE. The PE may be connected to the PE terminal (if provided) on the enclosure (if metallic and separated from internal wiring acc. to protection class II.

The phrases
"Dieses hat keinen Einfluss auf den Ansteuerkreis des Schalters, wenn dessen Steueranschluss gegenüber dem Massepotential mit einer Spannung beaufschlagt wird."
and
"Bei Halbleitertypen, die nicht gegen das Massepotential angesteuert werden, ...."

should be understand as

"This does not impact the switch control circuit, when the control terminal is subjected to a voltage with respect to the enclosure potential."
and
"For semiconductor types that are not driven against the enclosure potential, ....".

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Each different "ground" has its own symbol and application. See below:

# IEC-style ground (GND) symbol
# Signal/Low noise ground (GND) symbol
# IEC-style chassis-ground symbol
https://en.wikipedia.org/wiki/Electronic_symbol

The French page has the following symbols:

# Masse
# Protection Classe III
# Très basse tension Protection Classe II
# Double isolation Protection Classe I
# Mise à la terre Point équipotentiel (terre)
Terre
https://fr.wikipedia.org/wiki/Symbole_électronique

Same as in German:

# Schaltzeichen für Erde (allgemein) (Zeichen 02-15-01 aus der EN-60617-Reihe)
# Funktionserdung, fremdspannungsarme Erde (Zeichen 02-15-02 aus der EN-60617-Reihe)
# Schutzerdung (Zeichen 02-15-03 aus der EN-60617-Reihe)
# Schutzklasse 1 fett.svg Schutzerdung (Zeichen 02-15-03 aus der EN-60617-Reihe)
# Masse Gehäuse.PNG Masse, Gehäuse (Zeichen 02-15-04 aus der EN-60617-Reihe)
# Equipotential.svg Äquipotential (Zeichen 02-15-05 aus der EN-60617-Reihe)
https://de.wikipedia.org/wiki/Liste_der_Schaltzeichen_(Elekt...

# Zeichen 02-15-04 nach DIN EN 60617-2 für Masse, Gehäuse
# Zeichen 02-15-04 nach DIN EN 60617-2 für Masse, Gehäuse mit breiter Linie fürs Gehäuse, wenn keine Unklarheit besteht
Äquipotential
https://de.wikipedia.org/wiki/Masse_(Elektronik)

Same in Britannia:

BS EN 60617 SYMBOLS BS EN 60617 gives the graphical symbols that should be used in all electrical/electronic diagrams or drawings. Since the symbols fall in line with the International Electrotechnical Commission (IEC) document 617, it should be possible to interpret non-UK diagrams. Samples of the symbols in this book are shown in Figure 1.1
Earth and frame connections
# Earth or ground, general symbol
# Frame, chassis
https://books.google.de/books?id=kdn0SREeVQQC&pg=PA1&lpg=PA1...

See also:
http://www.roymech.co.uk/Useful_Tables/Drawing/Electical_Con...

In analog design, the relationship of a signal to ground is of fundamental concern (and can create issues in digital designs, too.) However, “ground” as a concept can be confusing as it relates to three different situations: chassis ground, signal ground, or earth ground. All three indicate connecting to a point of (theoretically) zero voltage, but within a different context: chassis ground for a device, signal ground for very low voltage signals within a device, and earth ground for a power system.
Figure 1: There are three different electrical symbols for ground, indicating context within a schematic. Source: Wikipedia.
:
A chassis ground is a ground-collection point that connects to the metal enclosure of an electrical device. A chassis ground may be used for shielding and grounding to prevent electrical shock. Mains’ earth ground and the (theoretically) 0V power rails are all tied together and connected to the chassis at that one point. For example, with multilayer printed circuit boards, one or more of the conducting layers may be used as a chassis ground. A chassis ground is typically only made at one point. This prevents a return current path through an available but undesirable means and prevents current circulating through the chassis. Current circulating through the chassis can induce a “ground loop.” But if the chassis is only grounded at one point, current cannot flow through the chassis, and the relationship between magnetic flux and electricity cannot be exercised. Ground loops, which cause induced EMF (noise), are especially problematic for noise-sensitive applications such as instrumentation and audio.
https://www.analogictips.com/faq-ground-rules-earth-chassis-...

Conclusion: Symbol 02-15-04 symbols the "ground" referred to in the context, i.g. frame, chassis. Please do not mismatch with general ground/earth 02-15-01!