OPT100 technical specification

Table 1. OPT100 measurement specification
Parameter ¹	Range	Accuracy ² ³	Repeatability ³
Methane (CH₄)	0–10 000 ppm_v	±4 ppm or ±5 % of reading	10 ppm or 5 % of reading
Ethane (C₂H₆)	0–10 000 ppm_v	±10 ppm or ±5 % of reading	10 ppm or 5 % of reading ⁴
Ethylene (C₂H₄)	0–10 000 ppm_v	±4 ppm or ±5 % of reading	10 ppm or 5 % of reading
Acetylene (C₂H₂)	0–5000 ppm_v	±0.5 ppm or ±5 % of reading	1 ppm or 5 % of reading
Carbon monoxide (CO)	0–10 000 ppm_v	±4 ppm or ±5 % of reading	10 ppm or 5 % of reading
Carbon dioxide (CO₂)	0–10 000 ppm_v	±4 ppm or ±5 % of reading	10 ppm or 5 % of reading
Hydrogen (H₂)	0–5000 ppm_v	±15 ppm or ±10 % of reading	15 ppm or 10 % of reading
Moisture ⁵ (H₂O)	0–100 ppm_w ⁶	±2 ppm ⁷ or ±10 % of reading	Included in accuracy
Total gas pressure	0–2000 hPa	±10 hPa or ±2 % of reading	10 hPa or 5 % of reading

Table 2. OPT100 measurement operation
Property	Description/Value
Measurement cycle duration	1–1.5 h (typical)
Response time (T63)	One measurement cycle ⁸
Warm-up time until first measurement data available	Two measurement cycles
Initialization time to full accuracy	Two days
Data storage	At least 10 years ⁹
Expected operating life	> 15 years

Table 3. OPT100 field performance
Parameter	Typical variance to laboratory DGA¹⁰ ¹¹
Acetylene (C₂H₂)	±1 ppm or ±10 % of reading
Hydrogen (H₂)	±15 ppm or ±15 % of reading
Other measured gases	±10 ppm or ±10 % of reading
Moisture (H₂O)	±2 ppm or ±10 % of reading

Table 4. OPT100 calculated parameters
Property	Description/Value
Total dissolved combustible gases (TDCG)	Combined total of H₂, CO, CH₄, C₂H₆, C₂H₄, and C₂H₂
24 h average	Available for single gases, moisture, TDCG, and total gas pressure
Rate of change (ROC)	Available for single gases and TDCG for 24 h, 7 d, and 30 d periods
Gas ratios ¹²	Available ratios: CH₄/H₂ C₂H₂/C₂H₄ C₂H₂/CH₄ C₂H₆/C₂H₂ C₂H₄/C₂H₆ CO₂/CO

Table 5. OPT100 operating environment
Property	Description/Value
Transformer liquid type ¹³	Mineral oil or ester liquids
Required minimum fire point of insulation liquid ¹⁴	+125 °C (+257 °F)
Transformer oil pressure at oil inlet	Max. 2 bar (absolute) continuous Burst pressure 20 bar (absolute)
Transformer insulation liquid temperature at oil inlet	Max. +100 °C (+212 °F) Min. +0 °C (+32 °F) for ester liquids Min. temperature for mineral oil depends on the pour point of the mineral oil.
Ambient humidity range	0–100 %RH, condensing
Ambient temperature range in operation	−40 … +55 °C (−40 … +131 °F)
Storage temperature range	−40 … +60 °C (−40 … +140 °F)
IP rating	IP66: Dust-tight. Protected from powerful water jets from any direction.

Table 6. OPT100 power supply
Property	Description/Value
Operating voltage	OPTPSU1: 100–240 V AC, 50–60 Hz, ±10 % OPTPSU2: 110–220 V DC, ±10 %
Overvoltage category	III
Maximum power consumption	500 W
Typical power consumption at +25 °C (+77 °F)	100 W
Connector	Screw terminals (inside power supply unit) Wire size 2.5–4 mm² (14–12 AWG)

Table 7. OPT100 outputs
Property	Description/Value
RS-485 interface
Connector	Screw terminals (inside OPT100 housing) Wire size 0.5–4 mm² (20–12 AWG)
Supported protocols	Modbus RTU, DNP3 (optional feature)
Galvanic isolation	2 kV RMS, 1 min
Ethernet interface
Connector	Industrial RJ45 connector with protective plug (outside OPT100 housing)
Supported protocols	Modbus TCP, HTTP, HTTPS, DNP3 (optional feature), IEC 61850 (optional feature)
Standard	IEEE 802.3
Physical layer	Base-T
Data rate	10/100 Mbps
Galvanic isolation	4 kV AC (50 Hz, 1 min)
Insulation voltage	250 V_rms
Relay outputs
Number of relays	3 pcs, normally open (NO) or normally closed (NC), user‑ selectable
Trigger type	Gas alert with user‑selectable limits
Connector	Screw terminals (inside power supply unit housing) Wire size 0.5–4 mm² (20–12 AWG)
Max. switching current	6 A (at 250 V AC) 2 A (at 24 V DC) 0.2 A (at 250 V DC)
Min. switching voltage	12 V DC (at 10 mA)
Min. switching current	10 mA (at 12 V)
Contact type	1 PDT
Auxiliary device interface
Maximum power	48 W
Voltage output	24 V DC
User interface
Interface type	Web‑based user interface, can be operated with standard web browsers
Connector for service use	RJ45 connector, inside OPT100 housing (temporary local use only)

Table 8. OPT100 mechanical specifications
Property	Description/Value
Oil fitting	Stainless steel Swagelok® fitting for 10 mm (0.39 in) outer diameter tubing. See list of available accessories for adapters.
Max. length of oil pipe to transformer for mineral oil	Max. 10 m (33 ft) with 7 mm (0.28 in) inner diameter tubing ¹⁵ Max. 5 m (16 ft) with 4 mm (0.15 in) inner diameter tubing
Max. length of pipe to transformer for ester liquid	Max. 10 m (33 ft) with 8 mm (0.31 in) inner diameter tubing
Recommended oil pipe properties	10 mm (0.39 in) outer diameter 1–1.5 mm wall thickness (mineral oil devices) 1 mm wall thickness (ester liquid devices) Material stainless steel
Dimensions (H × W × D)
Installed with ground mounting set and weather shield	1630 × 675 × 453 mm (64 × 27 × 18 in)
Installed with wall mounting set and weather shield	1390 × 675 × 467 mm (55 × 27 × 18 in)
Installed with antivibration wall mounting set and weather shield	1395 × 683 × 541 mm (55 × 27 × 21 in)
Weight
OPT100 DGA Monitor	35 kg (77 lb)
OPTPSU Power Supply Unit	12 kg (27 lb)
OPTMSET1 Wall Mounting Set	8 kg (18 lb)
OPTMSET2 Ground Mounting Set	16 kg (35 lb)
OPTMSET3 Antivibration Wall Mounting Set	9 kg (20 lb)
OPTSHLD1 Weather shield	6 kg (13 lb)
Materials
OPT100 DGA Monitor housing	Marine aluminum (EN AW-5754), stainless steel AISI 316
OPTPSU Power Supply Unit housing	Stainless steel
OPTMSET1 Wall Mounting Set	Stainless steel AISI 316
OPTMSET2 Ground Mounting Set	Stainless steel
OPTMSET3 Antivibration Wall Mounting Set	Stainless steel
OPTSHLD1 Weather Shield	Marine aluminum (EN AW-5754)
Materials in contact with oil
Oil pipes, chambers, and valves	Aluminum (EN AW 6026), stainless steel AISI 316, brass
Gaskets and seals	NBR, FKM, FVMQ
Pump gears and bushing	PEEK/PTFE

Table 9. OPT100 compliance
Property	Description/Value
EU directives and regulations	EMC Directive (2014/30/EU) Low Voltage Directive (2014/35/EU)
	OPT100 is specifically designed to be installed as part of another type of equipment that is excluded from the RoHS directive (2011/65/EU) scope.
EMC immunity	EN 61326‑1, industrial environment IEC 61000-6-5, class 4
EMC emissions	FCC 47 CFR 15, section 15.107, class A ISED ICES-003, section 5(a)(i), class A
Safety	IEC/EN/UL/CSA‑C22.2 61010‑1
Environmental	IEC 60068‑2‑1 IEC 60068‑2‑2 ISO 6270-1:2017, constant humidity condensation atmosphere, C5 ISO 9227:2017, salt fog, C5 IEC 61010-1:2010/AMD1:2016, pollution degree 4 (outdoor), 3 (industrial area), 2 (device internal)
Compliance marks	CE, China RoHS, EAC, RCM

¹ ppm values are defined as μl/l according to IEC 60567 standard conditions.

² Accuracy specified is the accuracy of the sensors during calibration gas measurements.

³ Whichever is greater.

⁴ Repeatability of ethane measurement is specified with averaging of five measurements.

⁵ Measured as relative saturation (%RS).

⁶ Upper range limited to saturation.

⁷ Calculated ppm value is based on average solubility of mineral oils.

⁸ Three cycles for ethane and hydrogen.

⁹ Data storage may run out of space after 20 years of measurements. To keep the old data, it is recommended to download it every 10 years.

¹⁰ Compared with gas chromatography result from an oil sample considering also laboratory uncertainty. Performance of the gas-in-oil measurement may also be affected by oil properties and other chemical compounds dissolved in oil.

¹¹ ppm values are defined as μl/l according to IEC 60567 standard conditions.

¹² Calculated from 24 h average values. See standard IEC 60599.

¹³ Selected when ordering the device.

¹⁴ "The fire point [of transformer oil] is normally approximately 10 °C [18 °F] higher than the closed flash point." Heathcote, Martin J. The J & P Transformer Book. 13th ed. Elsevier, 2007.

¹⁵ Bigger pipe volume will increase response time.

OPT100 technical specification - OPT100

OPT100 User Guide