RSE-0501-5

GAS DETECTOR HEAD
GD-F88Ai(Oxygen Deficiency Alarm) SPECIFICATION
ModelDetection principle
Gas to be detected
Concentration display
Detection range
Detection method
Alarm preset point*1
Indicate accuracy*2

GD-F88Ai
Galvanic cell method
O27-segment LCD (4 digits)
0～25vol%
Diffusion type18vol%(1st<L>)【Standard】
18vol%(2nd<LL>)【Standard】
Within ±0.7vol%(under an identical condition)

Response time*2

Within 30sec(T90)(under an identical condition)

Accuracy of Alarm setpoint＊2

Difference between Alarm setpoint and indicated value of warning alarm
are zero.
Alarm-delay time*2
By anoxia alarm(Alarm setpoint value:18vol%), Within 5sec(when(under an identical condition)
introducing 10～11vol% gas)
Gas alarm typeTwo-step alarm (L-LL)
Gas alarm indication
Alarm message(AL1/AL2)*1
Gas alarm action
Latching or non latching
Trouble alarm･Self diagnosis System failure/Sensor failure
Trouble alarm indication
Content display
Trouble alarm action
Non latchingTransmission method
2-wire analog transmission + digital transmission (HARTCommunication)
Transmission specifications
4-20mADC (load resistance: 300Ω or less)Communication scheme
HART 7
Power supply
24VDC±10%Power consumption
Approx. 0.6W
Transmission cable
Shielded cable of CVVS, etc. (1.25mm2) - 2-core
Transmission distance
Up to 1km with CVVS 1.25 mm2 (up to 600m between the detector head andZener Barrier)
Safety maintaining device*3
Zener Barrier (MTL7728ac/MTL7728+/MTL7728-) orinsulating barrier (MTL5541/RN221N-J1/KFD2-STC4-Ex1)
Operating temperature-10℃ to +40℃ (non-rapidly-vary)
Operating humidity
Less than 95%RH (non-condensing)
Structure
Wall mounted typeExplosion-proof structure
Intrinsically safe explosion-proof structure, with safety maintaining
device (barrier) used
Explosion-proof class
Ex ia ⅡC T4 Ga
External dimensions
Approx. 100(W)x241(H)x48(D)mm (projection portions excluded)
WeightApprox. 1.0kg
Material*1
SECC or SUS304
Paint
Bake-coated with melamine
Outer color
Munsell 2.5Y9/2*1 Please specify your request when ordering.
*2 In conformity to JIS T8201 2010(Oxygen deficiency indicator).
*3 Recommended item

RSE-0501-5

Outline Drawings

DisplaySensor

Nameplate

Nameplate

Cable inletφ9-φ14

Terminal Drawings

Groundingterminal＋ －Power supply andOutput signal
4-20mAwithHARTRSE-0713-4

GAS DETECTOR HEAD
GD-F88Ai(Gas monitoring) SPECIFICATION
ModelDetection principle
Gas to be detected
Concentration display
Detection range
Detection method
Alarm preset point*1
Indicate accuracy

GD-F88Ai
Galvanic cell method
O27-segment LCD (4 digits)
0～5vol%/0～10vol%/0～25vol%
Diffusion type
Depend on measuring range
Within ±0.7vol%(below 25vol% range)(under an identical condition)

Response time

Within 30sec(T90)(under an identical condition)

Gas alarm type*1
Gas alarm indication
Gas alarm action*1
Trouble alarm･Self diagnosis
Trouble alarm indication
Trouble alarm action
Transmission method
Transmission specifications
Communication schemePower supply
Power consumption
Transmission cable
Transmission distanceTwo-step alarm (H-HH, L-H, and L-LL)
Alarm message(AL1/AL2)
Latching or non latching
System failure/Sensor failure
Content display
Non latching
2-wire analog transmission + digital transmission (HART Communication)
4-20mADC (load resistance: 300Ω or less)
HART 7
24VDC±10%
Approx. 0.6W
Shielded cable of CVVS, etc. (1.25mm2) - 2-core
Up to 1km with CVVS 1.25 mm2 (up to 600m between the detector head andZener Barrier)
Safety maintaining device*2
Zener Barrier (MTL7728ac/MTL7728+/MTL7728-) or
insulating barrier (MTL5541/RN221N-J1/KFD2-STC4-Ex1)
Operating temperature-10℃ to +40℃ (non-rapidly-vary)
Operating humidity
Less than 95%RH (non-condensing)
Structure
Wall mounted type
Explosion-proof structure
Intrinsically safe explosion-proof structure, with safety maintainingdevice (barrier) used
Explosion-proof classEx ia ⅡC T4 Ga
External dimensions
Approx. 100(W)x241(H)x48(D)mm (projection portions excluded)
WeightApprox. 1.0kg
Material*1
SECC or SUS304
Paint
Bake-coated with melamine
Outer color
Munsell 2.5Y9/2*1 Please specify your request when ordering.
*2 Recommended item

RSE-0713-4

Outline Drawings

Display

SensorNameplate

Nameplate

Cable inlet
φ9-φ14

Terminal Drawings

Groundingterminal＋ －Power supply andOutput signal
4-20mAwithHART