Riken Keiki GD-3EC, Technical Manual

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2. Important Safety Information 2-4 Safety information
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2-4 Safety information
<Product overview>

The products have an explosion-proof construction.

Sensors are divided into three different types, depending on the corresponding detection principles. The
detection methods are divided into the diffusion type and suction type. Suction-type sensors should be used
with a suction cap fitted.

The product is a fixed, continuous monitoring detector. It can be connected to a gas monitoring control unit,
recorder, or programmable control unit to output the measured gas readings as a 4 - 20 mA signal or HART
signal.

The following three sets of output specifications are available for this product:
・
No alarm relay, no digital communication
・
3 alarm relays (contact output) (alarm relays operate in conjunction with gas alarms and faults), no
digital signal
・
No alarm relay, digital communication (RS-485 output)

The electrochemical sensor is made into an explosion-proof construction by using an EC barrier.
<Detection principles and models>

The models corresponding to the individual detection principles are as follows. The models are classified by
detection principle and detection method.
Detection principle (Detection method: Diffusion type) Model
Optical sensor Non-dispersive infrared absorption type (infrared
type) SD-3RI
Solid state sensor Semiconductor type SD-3GH
SD-3GHS
New ceramic type SD-3NC
Hot-wire semiconductor type SD-3SP
Electrochemical sensor Electrochemical type SD-3EC
SD-3ECS
SD-3ECB
Detection principle (Detection method: Suction type) Model
Optical sensor Non-dispersive infrared absorption type (infrared
type) SD-3DRI
Solid state sensor Semiconductor type SD-3DGH
SD-3DGHS
New ceramic type SD-3DNC
Hot-wire semiconductor type SD-3DSP
Electrochemical sensor Electrochemical type SD-3DEC
SD-3DECS
SD-3DECB