Elmwood D Series

Elmwood D Series are based on reliable one-shot operation and protect electrical appliance against overheating.

Thermal Cut Offs (TCO) responds to temperature by interrupting an electrical circuit when the operating and /or environmental temperature exceeds the thermal rating of the fuse. This is accomplished when the organic pellet experience a phase change, allowing the spring activated contacts to permanently open the circuit. Once activated the electrical circuit remain permanently open.

D SERIES TEMPERATURE RATING

MODEL Tf (FUNCTIONING OPEN TEMPERATURE) Th (HOLDING TEMPERATURE) Tm (MAXIMUM OVERSHOOT TEMPERATURE) SAFETY APPROVAL
D070 72 162 +0/-4℃ 57 115 UL, C-UL, VDE, NEMKO, SEMKO, CCC, PSE
D076 77 171 +0/-4℃ 62 150
D081 84 183 +0/-4℃ 69 115
D088 90 194 +0/-4℃ 75 150
D090 93 199 +0/-6℃ 78 315
D098 100 212 +0/-4℃ 85 130
D103 104 219 +0/-4℃ 89 315
D108 109 228 +0/-4℃ 94 215 (VDE, CCC,SEMKO,NEMKO)
315 (UL,C-UL)
D110 110 230 +0/-4℃ 95 150
D115 117 243 +0/-4℃ 102 130
D118 121 250 +0/-6℃ 106 315
D125 128 262 +0/-4℃ 113 300 (VDE,SEMKO,NEMKO)
180 (UL, C-UL, CCC)
D139 141 286 +0/-6℃ 126 170 (VDE,SEMKO,NEMKO)
230 (UL, C-UL, CCC)
D142 144 291 +0/-6℃ 129 315 (VDE,SEMKO,NEMKO)
240 (UL, C-UL, CCC)
D156 156 313 +0/-6℃ 141 170
D165 169 336 +0/-6℃ 154 270 (120V), 250 (250V) (VDE,SEMKO,NEMKO)
270(120V), 210 (250V)  (UL, C-UL, CCC)
D172 172 342 +0/-5℃ 157 280
D181 184 363 +0/-4℃ 169 210
D192 192 378 +0/-5℃ 182 250
D213 216 421 +0/-4℃ 201 375
D226 228 442 +0/-6℃ 212 260(120V) 240(250V)
D230 230 446 +0/-6℃ 212 375
D242 240 464 +0/-6℃ 215 375
D257 257 495 +0/-5℃ 220 375


Tf (FUNCTIONING OPEN TEMPERATURE)
The maximum temperature at which the thermal cut offs changes its state of conductivity
to open circuit with detection current as the only load.

Th (HOLDING TEMPERATURE)
The maximum temperature at which,when applying no electrical load to the thermal cut offs,
the state of conductivity will not change during a period of 168 hours.

Tm (MAXIMUM OVERSHOOT TEMPERATURE)
The maximum temperature of thermal cut offs, having changed its state of conductivity, can be maintained for 10 minutes
during which its mechanical and electrical properties will not be impaired.

ELECTRICAL RATINGS

AC Electrical Rating

Standard Ratings (Except specific type listed below from *1 to *6)

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, NEMKO, SEMKO, CCC 120V / 250V 16.7A / 16.7A 25A / 25A

 

*1 D090

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, CCC 120V / 250V 16.7A / 16.7A 25A / 25A
NEMKO, SEMKO 120V / 250V 16.7A / 10A 25A / 15A

 

*2 D115

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, NEMKO 120V / 250V 16.7A / 16.7A 25A / 25A
CCC, SEMKO 120V / 250V 16.7A / 10A 25A / 15A

 

*3 D139

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, NEMKO, SEMKO, CCC 120V 16.7A 25A

 

*4 D172

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, CCC, NEMKO 120V / 250V 16.7A / 16.7A 25A / 25A
SEMKO 120V / 250V 16.7A / 10A 25A / 15A

 

*5 D192

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, NEMKO 120V / 250V 16.7A / 16.7A 25A / 25A
VDE, CCC, SEMKO 120V / 250V 16.7A / 10A 25A / 15A

 

*6 D213

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL 120V / 250V 16.7A / 16.7A 25A / 25A
VDE, SEMKO, NEMKO, CCC 120V / 250V 16.7A / 12A 25A / 18A

 

*7 D156, D257

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, SEMKO 120V / 250V 15A / 10A 22A / 15A

  

*8 DXXX PSE Electrical Rating

SAFETY APPROVAL VOLTAGE (AC) RESISTIVE CURRENT
(Vr) (Ir)
PSE 125V 15A


DC Electrical Rating

Standard Ratings (Except specific type listed below **)

SAFETY APPROVAL VOLTAGE (DC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, SEMKO, NEMKO 12V / 24V 10A / 5A 15A / 7.5A

 

** D192, D226

SAFETY APPROVAL VOLTAGE (DC) RESISTIVE CURRENT
(Vr) (Ir) (Ib)
UL, C-UL, VDE, SEMKO, NEMKO, CCC 12V / 24V 10A / 5A 15A / 7.5A


<Notes> All products shall comply with IEC-60691 - FOR ED. 3.0 AMENDMENT 2.

INSTALLATION

The performance of the Elmwood Thermal Cut Offs requires proper handling during installation for it to operate in its intended manner. These installations are intended to be used to reduce the risk of malfunction of the thermal cut off which may result from improper installation during forming of leads, splicing, welding and soldering.

 

1. BENDING LEADS

Care should be taken when forming the Thermal Cut Offs (TCO) leads. The TCO leads must be supported 1/8" from bend and case; and 1/8" from bend and epoxy. This will prevent the epoxy seal from cracking which may result in premature degradation of the pellet. A close visual inspection should be performed to make sure that the TCO leads have not been cut, nicked, folded sharply, fractured or burned.

 

2. MECHANICAL FORCES DURING APPLIANCE CONNECTION

a. When installing the TCO, avoid unnecessary bending, twisting, pulling or pushing on the TCO leads. Care should be taken to avoid cracking or chipping of the epoxy which may result from sharp twisting or bending of the lead.

b. The TCO body must maintain its cylindrical shape to function properly. Excessive clamping could cause denting or crushing of the TCO body, which may lead to failure. X-ray and visual inspection of the TCO will determine if the fuse body has been damaged.

c. Note that the TCO body is electrically live and must be insulated before applying a metal clamp over the TCO body.

d. Care should be used when pushing the epoxy end lead, to avoid the lead being forced into the TCO body. This could result in failure.

 

3. SPLICE AND TERMINATIONS

By attaching free wire to the TCO leads, connections can be made by bending the free wire ; and keeping the TCO leads from being subjected to undue stresses. Splices should be sized according to the size of the wire plus the TCO lead wire. The connections must be electrically sound to prevent high resistance and secure enough to withstand the rated cutoff temperature. Improper connections may cause damage to the seal or other parts and may result in nuisance tripping of the devices due to the generation of excessive heat at a faulty high resistance junction. High resistance junctions may form after normal operation of end use equipment and if the TCO has been subjected to several high temperature cycles. Lead connections used at 150℃ (302°F) or higher should be soldered or welded.

 

4. SOLDERING LEAD

The TCO leads require heat sinking during soldering operations. Lower temperature rated fuses may require more heat sinking than do higher rated fuses. Samples should be X-rayed before and after soldering to insure a consistent pellet height. Reduction of dimension of the thermal pellet indicates that more heat sinking is required. Also, excessive heat conducted by the leads could shorten the life of the TCO as well as burn the epoxy. Assure that the leads are supported during soldering to avoid breaking or cracking of the epoxy.

 

5. WELDING LEADS

Excessive heat from resistance welding should not be conducted to the body of the TCO. To avoid welding, internal parts, care should be taken that none of the welding current is conducted through the TCO. A welding current of hundreds of amperes could weld the internal parts together resulting in a failure. The leads must also be supported during welding to avoid breaking or cracking of the epoxy.

 

6. PROTECTION AGAINST OVERHEATING

A certain amount of heat is transmitted to the body of the TCO through the connecting lead on some applications. By attaching the epoxy lead to the heat source, you thereby minimize the temperature increase of the TCO body from this heat flow. When locating the TCO near a heat source, the device should be protected from overheating during operation. Normal operation overheating may cause premature opening of the device and excess overshoot may cause damage to the thermal cutoff. Under general application environment, ELMWOOD suggest the temperature of the case of TCO shall be below 30℃ from controlled temperature at a certain application.

 

7. EXAMINATION FOR DAMAGE

An examination for damage of the thermal cut off should be done after the device-to-appliance connections are made. X-raying before and after the assembly operation and close visual inspection ; with special attention made at the epoxy, should be performed on early production samples.

 

REPLACEMENT

It should be made clear for reasons of safety, that a TCO is a non-repairable item and that in case of replacement an equivalent TCO with the same catalogue number shall be used and mounted in exactly the same way.